1
|
Huynh MT, Erfani Z, Kovács Z, Park JM. Hyperpolarized [2- 13C, 3- 2H 3]Pyruvate Detects Hepatic Gluconeogenesis In Vivo. ACS Sens 2024; 9:2801-2805. [PMID: 38838349 PMCID: PMC11227886 DOI: 10.1021/acssensors.4c00734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
The feasibility of hyperpolarized [2-13C, 3-2H3]pyruvate for probing gluconeogenesis in vivo was investigated in this study. Whereas hyperpolarized [1-13C]pyruvate has clear access to metabolic pathways that convert pyruvate to lactate, alanine, and bicarbonate, its utility for assessing pyruvate carboxylation and gluconeogenesis has been limited by technical challenges, including spectral overlap and an obscure enzymatic step that decarboxylates the labeled carbon. To achieve unambiguous detection of gluconeogenic products, the carbonyl carbon in pyruvate was labeled with 13C. To prolong the T1 relaxation time, [2-13C, 3-2H3]pyruvate was synthesized and dissolved with D2O after dynamic nuclear polarization. The T1 of [2-13C, 3-2H3]pyruvate in D2O could be improved by 76.9% (79.6 s at 1 T and 74.5 s at 3 T) as compared to [2-13C]pyruvate in water. Hyperpolarized [2-13C, 3-2H3]pyruvate with D2O dissolution was applied to rat livers in vivo under normal feeding and fasting conditions. A gluconeogenic product, [2-13C]phosphoenolpyruvate, was observed at 149.9 ppm from fasted rats only, highlighting the utility of [2-13C, 3-2H3]pyruvate in detecting key gluconeogenic enzyme activities such as pyruvate carboxylase and phosphoenolpyruvate carboxykinase in vivo.
Collapse
Affiliation(s)
- Mai T Huynh
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Zohreh Erfani
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Zoltán Kovács
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| | - Jae Mo Park
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Department of Biomedical Engineering, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
- Department of Radiology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390, United States
| |
Collapse
|
2
|
Adelabu I, Nantogma S, Fleischer S, Abdulmojeed M, de Maissin H, Schmidt AB, Lehmkuhl S, Rosen MS, Appelt S, Theis T, Qian C, Chekmenev EY. Toward Ultra-High-Quality-Factor Wireless Masing Magnetic Resonance Sensing. Angew Chem Int Ed Engl 2024:e202406551. [PMID: 38822492 DOI: 10.1002/anie.202406551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 05/16/2024] [Accepted: 05/31/2024] [Indexed: 06/03/2024]
Abstract
It has recently been shown that a bolus of hyperpolarized nuclear spins can yield stimulated emission signals similar in nature to maser signals, potentially enabling new ways of sensing hyperpolarized contrast media, including most notably [1-13C]pyruvate that is under evaluation in over 50 clinical trials for metabolic imaging of cancer. The stimulated NMR signal emissions lasting for minutes do not require radio-frequency excitation, offering unprecedented advantages compared to conventional MR sensing. However, creating nuclear spin maser emission is challenging in practice due to stringent fundamental requirements, making practical in vivo applications hardly possible using conventional passive MR detectors. Here, we demonstrate the utility of a wireless NMR maser detector, the quality factor of which was enhanced 22-fold (to 1,670) via parametric pumping. This active-feedback technique breaks the intrinsic fundamental limit of NMR detector circuit quality factor. We show the use of parametric pumping to reduce the threshold requirement for inducing nuclear spin masing at 300 MHz resonance frequency in a preclinical MRI scanner. Indeed, stimulated emission from hyperpolarized protons was obtained under highly unfavorable conditions of low magnetic field homogeneity (T2* of 3 ms). Greater gains of the quality factor of the MR detector (up to 1 million) were also demonstrated.
Collapse
Affiliation(s)
- Isaiah Adelabu
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan, 48202, United States
| | - Shiraz Nantogma
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan, 48202, United States
| | - Simon Fleischer
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344, Eggenstein-Leopoldshafen, Karlsruhe, Germany
| | - Mustapha Abdulmojeed
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27695-8204, United States
| | - Henri de Maissin
- Division of Medical Physics, Department of Radiology, Medical Center, Faculty of Medicine, University of Freiburg, Killianstr. 5a, Freiburg, 79106, Germany
- German Cancer Consortium (DKTK), Partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Andreas B Schmidt
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan, 48202, United States
- Division of Medical Physics, Department of Radiology, Medical Center, Faculty of Medicine, University of Freiburg, Killianstr. 5a, Freiburg, 79106, Germany
- German Cancer Consortium (DKTK), Partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg, 69120, Germany
| | - Soeren Lehmkuhl
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, 76344, Eggenstein-Leopoldshafen, Karlsruhe, Germany
| | - Matthew S Rosen
- Massachusetts General Hospital, A. A. Martinos Center for Biomedical Imaging, Boston, Massachusetts, 02129, United States
- Department of Physics, Harvard University, Cambridge, Massachusetts, 02138, United States
| | - Stephan Appelt
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52056, Aachen, Germany
- Central Institute for Engineering, Electronics and Analytics-Electronic Systems (ZEA-2), Forschungszentrum Jülich GmbH, D-52425, Jülich, Germany
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina, 27695-8204, United States
| | - Chunqi Qian
- Department of Radiology, Michigan State University, East Lansing, Michigan, 48824, United States
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, Detroit, Michigan, 48202, United States
| |
Collapse
|
3
|
Rushin A, McLeod MA, Ragavan M, Merritt ME. Observing exocrine pancreas metabolism using a novel pancreas perfusion technique in combination with hyperpolarized [1- 13 C]pyruvate. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:748-758. [PMID: 37482899 PMCID: PMC10800648 DOI: 10.1002/mrc.5382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 06/28/2023] [Accepted: 07/06/2023] [Indexed: 07/25/2023]
Abstract
In a clinical setting, ex vivo perfusions are routinely used to maintain and assess organ viability prior to transplants. Organ perfusions are also a model system to examine metabolic flux while retaining the local physiological structure, with significant success using hyperpolarized (HP) 13 C NMR in this context. We use a novel exocrine pancreas perfusion technique via the common bile duct to assess acinar cell metabolism with HP [1-13 C]pyruvate. The exocrine component of the pancreas produces digestive enzymes through the ductal system and is often neglected in research on the pancreas. Real-time production of [1-13 C]lactate, [1-13 C]alanine, [1-13 C]malate, [4-13 C]malate, [1-13 C]aspartate, and H13 CO3 - was detected. The appearance of these resonances indicates flux through both pyruvate dehydrogenase and pyruvate carboxylase. We studied excised pancreata from C57BL/6J mice and NOD.Rag1-/- .AI4α/β mice, a commonly used model of Type 1 Diabetes (T1D). Pancreata from the T1D mice displayed increased lactate to alanine ratio without changes in oxygen consumption, signifying increased cytosolic NADH levels. The mass isotopologue analysis of the extracted pancreas tissue using gas chromatography-mass spectrometry revealed confirmatory 13 C enrichment in multiple TCA cycle metabolites that are products of pyruvate carboxylation. The methodology presented here has the potential to provide insight into mechanisms underlying several pancreatic diseases, such as diabetes, pancreatitis, and pancreatic cancer.
Collapse
Affiliation(s)
- Anna Rushin
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Marc A. McLeod
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Mukundan Ragavan
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA
| | - Matthew E. Merritt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, Florida, USA
| |
Collapse
|
4
|
Yiew NK, Deja S, Ferguson D, Cho K, Jarasvaraparn C, Jacome-Sosa M, Lutkewitte AJ, Mukherjee S, Fu X, Singer JM, Patti GJ, Burgess SC, Finck BN. Effects of hepatic mitochondrial pyruvate carrier deficiency on de novo lipogenesis and gluconeogenesis in mice. iScience 2023; 26:108196. [PMID: 37942005 PMCID: PMC10628847 DOI: 10.1016/j.isci.2023.108196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 07/31/2023] [Accepted: 10/10/2023] [Indexed: 11/10/2023] Open
Abstract
The liver coordinates the systemic response to nutrient deprivation and availability by producing glucose from gluconeogenesis during fasting and synthesizing lipids via de novo lipogenesis (DNL) when carbohydrates are abundant. Mitochondrial pyruvate metabolism is thought to play important roles in both gluconeogenesis and DNL. We examined the effects of hepatocyte-specific mitochondrial pyruvate carrier (MPC) deletion on the fasting-refeeding response. Rates of DNL during refeeding were impaired by hepatocyte MPC deletion, but this did not reduce intrahepatic lipid content. During fasting, glycerol is converted to glucose by two pathways; a direct cytosolic pathway and an indirect mitochondrial pathway requiring the MPC. Hepatocyte MPC deletion reduced the incorporation of 13C-glycerol into TCA cycle metabolites, but not into new glucose. Furthermore, suppression of glycerol and alanine metabolism did not affect glucose concentrations in fasted hepatocyte-specific MPC-deficient mice, suggesting multiple layers of redundancy in glycemic control in mice.
Collapse
Affiliation(s)
- Nicole K.H. Yiew
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Stanislaw Deja
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390, USA
| | - Daniel Ferguson
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Kevin Cho
- Department of Chemistry, Siteman Cancer Center, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Chaowapong Jarasvaraparn
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Miriam Jacome-Sosa
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Andrew J. Lutkewitte
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Sandip Mukherjee
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Xiaorong Fu
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390, USA
| | - Jason M. Singer
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Gary J. Patti
- Department of Chemistry, Siteman Cancer Center, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Shawn C. Burgess
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390, USA
| | - Brian N. Finck
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, St. Louis, MO 63110, USA
| |
Collapse
|
5
|
Shaul D, Lev-Cohain N, Sapir G, Sosna J, Gomori JM, Joskowicz L, Katz-Brull R. Real-time influence of intracellular acidification and Na + /H + exchanger inhibition on in-cell pyruvate metabolism in the perfused mouse heart: A 31 P-NMR and hyperpolarized 13 C-NMR study. NMR IN BIOMEDICINE 2023; 36:e4993. [PMID: 37424280 DOI: 10.1002/nbm.4993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 05/31/2023] [Accepted: 06/01/2023] [Indexed: 07/11/2023]
Abstract
Disruption of acid-base balance is linked to various diseases and conditions. In the heart, intracellular acidification is associated with heart failure, maladaptive cardiac hypertrophy, and myocardial ischemia. Previously, we have reported that the ratio of the in-cell lactate dehydrogenase (LDH) to pyruvate dehydrogenase (PDH) activities is correlated with cardiac pH. To further characterize the basis for this correlation, these in-cell activities were investigated under induced intracellular acidification without and with Na+ /H+ exchanger (NHE1) inhibition by zoniporide. Male mouse hearts (n = 30) were isolated and perfused retrogradely. Intracellular acidification was performed in two ways: (1) with the NH4 Cl prepulse methodology; and (2) by combining the NH4 Cl prepulse with zoniporide. 31 P NMR spectroscopy was used to determine the intracellular cardiac pH and to quantify the adenosine triphosphate and phosphocreatine content. Hyperpolarized [1-13 C]pyruvate was obtained using dissolution dynamic nuclear polarization. 13 C NMR spectroscopy was used to monitor hyperpolarized [1-13 C]pyruvate metabolism and determine enzyme activities in real time at a temporal resolution of a few seconds using the product-selective saturating excitation approach. The intracellular acidification induced by the NH4 Cl prepulse led to reduced LDH and PDH activities (-16% and -39%, respectively). This finding is in line with previous evidence of reduced myocardial contraction and therefore reduced metabolic activity upon intracellular acidification. Concomitantly, the LDH/PDH activity ratio increased with the reduction in pH, as previously reported. Combining the NH4 Cl prepulse with zoniporide led to a greater reduction in LDH activity (-29%) and to increased PDH activity (+40%). These changes resulted in a surprising decrease in the LDH/PDH ratio, as opposed to previous predictions. Zoniporide alone (without intracellular acidification) did not change these enzyme activities. A possible explanation for the enzymatic changes observed during the combination of the NH4 Cl prepulse and NHE1 inhibition may be related to mitochondrial NHE1 inhibition, which likely negates the mitochondrial matrix acidification. This effect, combined with the increased acidity in the cytosol, would result in an enhanced H+ gradient across the mitochondrial membrane and a temporarily higher pyruvate transport into the mitochondria, thereby increasing the PDH activity at the expense of the cytosolic LDH activity. These findings demonstrate the complexity of in-cell cardiac metabolism and its dependence on intracellular acidification. This study demonstrates the capabilities and limitations of hyperpolarized [1-13 C]pyruvate in the characterization of intracellular acidification as regards cardiac pathologies.
Collapse
Affiliation(s)
- David Shaul
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- The Wohl Institute for Translational Medicine, Hadassah Medical Organization, Jerusalem, Israel
| | - Naama Lev-Cohain
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Gal Sapir
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- The Wohl Institute for Translational Medicine, Hadassah Medical Organization, Jerusalem, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - J Moshe Gomori
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Leo Joskowicz
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Rachel Katz-Brull
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
- The Wohl Institute for Translational Medicine, Hadassah Medical Organization, Jerusalem, Israel
| |
Collapse
|
6
|
Yiew NK, Deja S, Ferguson D, Cho K, Jarasvaraparn C, Jacome-Sosa M, Lutkewitte AJ, Mukherjee S, Fu X, Singer JM, Patti GJ, Burgess SC, Finck BN. Effects of hepatic mitochondrial pyruvate carrier deficiency on de novo lipogenesis and glycerol-mediated gluconeogenesis in mice. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.17.528992. [PMID: 36824879 PMCID: PMC9949129 DOI: 10.1101/2023.02.17.528992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The liver coordinates the systemic response to nutrient deprivation and availability by producing glucose from gluconeogenesis during fasting and synthesizing lipids via de novo lipogenesis (DNL) when carbohydrates are abundant. Mitochondrial pyruvate metabolism is thought to play important roles in both gluconeogenesis and DNL. We examined the effects of hepatocyte-specific mitochondrial pyruvate carrier (MPC) deletion on the fasting-refeeding response. Rates of DNL during refeeding were impaired by liver MPC deletion, but this did not reduce intrahepatic lipid content. During fasting, glycerol is converted to glucose by two pathways; a direct cytosolic pathway essentially reversing glycolysis and an indirect mitochondrial pathway requiring the MPC. MPC deletion reduced the incorporation of 13C-glycerol into TCA cycle metabolites but not into newly synthesized glucose. However, suppression of glycerol metabolism did not affect glucose concentrations in fasted hepatocyte-specific MPC-deficient mice. Thus, glucose production by kidney and intestine may compensate for MPC deficiency in hepatocytes.
Collapse
Affiliation(s)
- Nicole K.H. Yiew
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Stanislaw Deja
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390 USA
| | - Daniel Ferguson
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Kevin Cho
- Department of Chemistry, Siteman Cancer Center, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis, MO 63110 USA
| | - Chaowapong Jarasvaraparn
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Miriam Jacome-Sosa
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Andrew J. Lutkewitte
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Sandip Mukherjee
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Xiaorong Fu
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390 USA
| | - Jason M. Singer
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| | - Gary J. Patti
- Department of Chemistry, Siteman Cancer Center, Center for Metabolomics and Isotope Tracing, Washington University in St. Louis, MO 63110 USA
| | - Shawn C. Burgess
- Center for Human Nutrition, University of Texas Southwestern, Dallas, TX 75390 USA
| | - Brian N. Finck
- Department of Medicine, Center for Human Nutrition, Washington University in St. Louis, MO 63110 USA
| |
Collapse
|
7
|
Tavoulari S, Sichrovsky M, Kunji ERS. Fifty years of the mitochondrial pyruvate carrier: New insights into its structure, function, and inhibition. Acta Physiol (Oxf) 2023; 238:e14016. [PMID: 37366179 PMCID: PMC10909473 DOI: 10.1111/apha.14016] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/12/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023]
Abstract
The mitochondrial pyruvate carrier (MPC) resides in the mitochondrial inner membrane, where it links cytosolic and mitochondrial metabolism by transporting pyruvate produced in glycolysis into the mitochondrial matrix. Due to its central metabolic role, it has been proposed as a potential drug target for diabetes, non-alcoholic fatty liver disease, neurodegeneration, and cancers relying on mitochondrial metabolism. Little is known about the structure and mechanism of MPC, as the proteins involved were only identified a decade ago and technical difficulties concerning their purification and stability have hindered progress in functional and structural analyses. The functional unit of MPC is a hetero-dimer comprising two small homologous membrane proteins, MPC1/MPC2 in humans, with the alternative complex MPC1L/MPC2 forming in the testis, but MPC proteins are found throughout the tree of life. The predicted topology of each protomer consists of an amphipathic helix followed by three transmembrane helices. An increasing number of inhibitors are being identified, expanding MPC pharmacology and providing insights into the inhibitory mechanism. Here, we provide critical insights on the composition, structure, and function of the complex and we summarize the different classes of small molecule inhibitors and their potential in therapeutics.
Collapse
Affiliation(s)
- Sotiria Tavoulari
- Medical Research Council Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Maximilian Sichrovsky
- Medical Research Council Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| | - Edmund R. S. Kunji
- Medical Research Council Mitochondrial Biology UnitUniversity of CambridgeCambridgeUK
| |
Collapse
|
8
|
Liu X, Tang S, Cui D, Bok RA, Chen HY, Gordon JW, Wang ZJ, Larson PEZ. A metabolite specific 3D stack-of-spirals bSSFP sequence for improved bicarbonate imaging in hyperpolarized [1- 13C]Pyruvate MRI. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 353:107518. [PMID: 37402333 PMCID: PMC10498937 DOI: 10.1016/j.jmr.2023.107518] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/23/2023] [Accepted: 06/25/2023] [Indexed: 07/06/2023]
Abstract
13C-bicarbonate is a crucial measure of pyruvate oxidation and TCA cycle flux, but is challenging to measure due to its relatively low concentration and thus will greatly benefit from improved signal-to-noise ratio (SNR). To address this, we developed and investigated the feasibility of a 3D stack-of-spirals metabolite-specific balanced steady-state free precession (MS-bSSFP) sequence for improving the SNR and spatial resolution of dynamic 13C-bicarbonate imaging in hyperpolarized [1-13C]pyruvate studies. The bicarbonate MS-bSSFP sequence was evaluated by simulations, phantoms studies, preclinical studies on five rats, brain studies on two healthy volunteers and renal study on one renal cell carcinoma patient. The simulations and phantom results showed that the bicarbonate-specific pulse had minimal perturbation of other metabolites (<1%). In the animal studies, the MS-bSSFP sequence provided an approximately 2.6-3 × improvement in 13C-bicarbonate SNR compared to a metabolite-specific gradient echo (MS-GRE) sequence without altering the bicarbonate or pyruvate kinetics, and the shorter spiral readout in the MS-bSSFP approach reduced blurring. Using the SNR ratio between MS-bSSFP and MS-GRE, the T2 values of bicarbonate and lactate in the rat kidneys were estimated as 0.5 s and 1.1 s, respectively. The in-vivo feasibility of bicarbonate MS-bSSFP sequence was demonstrated in two human brain studies and one renal study. These studies demonstrate the potential of the sequence for in-vivo applications, laying the foundation for future studies to observe this relatively low concentration metabolite with high-quality images and improve measurements of pyruvate oxidation.
Collapse
Affiliation(s)
- Xiaoxi Liu
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | | | - Di Cui
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Robert A Bok
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Hsin-Yu Chen
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Jeremy W Gordon
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Zhen J Wang
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Peder E Z Larson
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA; Graduate Program in Bioengineering, University of California, Berkeley and San Francisco, San Francisco, CA, USA.
| |
Collapse
|
9
|
Sharma G, Maptue N, Rahim M, Trigo Mijes ML, Hever T, Wen X, Funk AM, Malloy CR, Young JD, Khemtong C. Oxidation of hyperpolarized [1- 13 C]pyruvate in isolated rat kidneys. NMR IN BIOMEDICINE 2023; 36:e4857. [PMID: 36285844 PMCID: PMC9980878 DOI: 10.1002/nbm.4857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 10/05/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Kidneys play a central role in numerous disorders but current imaging methods have limited utility to probe renal metabolism. Hyperpolarized (HP) 13 C magnetic resonance imaging is uniquely suited to provide metabolite-specific information about key biochemical pathways and it offers the further advantage that renal imaging is practical in humans. This study evaluated the feasibility of hyperpolarization examinations in a widely used model for analysis of renal physiology, the isolated kidney, which enables isolation of renal metabolism from the effects of other organs and validation of HP results by independent measurements. Isolated rat kidneys were supplied with either HP [1-13 C]pyruvate only or HP [1-13 C]pyruvate plus octanoate. Metabolic activity in both groups was confirmed by stable renal oxygen consumption. HP [1-13 C]pyruvate was readily metabolized to [13 C]bicarbonate, [1-13 C]lactate, and [1-13 C]alanine, detectable seconds after HP [1-13 C]pyruvate was injected. Octanoate suppressed but did not eliminate the production of HP [13 C]bicarbonate from [1-13 C]pyruvate. Steady-state flux analyses using non-HP 13 C substrates validated the utilization of HP [1-13 C]pyruvate, as observed by HP 13 C NMR. In the presence of octanoate, lactate is generated from a tricarboxylic acid cycle intermediate, oxaloacetate. The isolated rat kidney may serve as an excellent model for investigating and establishing new HP 13 C metabolic probes for future kidney imaging applications.
Collapse
Affiliation(s)
- Gaurav Sharma
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Nesmine Maptue
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA
| | - Mohsin Rahim
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
| | - Miriam L. Trigo Mijes
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Thomas Hever
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Xiaodong Wen
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Alexander M. Funk
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Craig R. Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
- VA North Texas Health Care System, Dallas, TX, USA
| | - Jamey D. Young
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Chalermchai Khemtong
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL, USA
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA
| |
Collapse
|
10
|
Yook JS, Taxin ZH, Yuan B, Oikawa S, Auger C, Mutlu B, Puigserver P, Hui S, Kajimura S. The SLC25A47 locus controls gluconeogenesis and energy expenditure. Proc Natl Acad Sci U S A 2023; 120:e2216810120. [PMID: 36812201 PMCID: PMC9992842 DOI: 10.1073/pnas.2216810120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 01/12/2023] [Indexed: 02/24/2023] Open
Abstract
Mitochondria provide essential metabolites and adenosine triphosphate (ATP) for the regulation of energy homeostasis. For instance, liver mitochondria are a vital source of gluconeogenic precursors under a fasted state. However, the regulatory mechanisms at the level of mitochondrial membrane transport are not fully understood. Here, we report that a liver-specific mitochondrial inner-membrane carrier SLC25A47 is required for hepatic gluconeogenesis and energy homeostasis. Genome-wide association studies found significant associations between SLC25A47 and fasting glucose, HbA1c, and cholesterol levels in humans. In mice, we demonstrated that liver-specific depletion of SLC25A47 impaired hepatic gluconeogenesis selectively from lactate, while significantly enhancing whole-body energy expenditure and the hepatic expression of FGF21. These metabolic changes were not a consequence of general liver dysfunction because acute SLC25A47 depletion in adult mice was sufficient to enhance hepatic FGF21 production, pyruvate tolerance, and insulin tolerance independent of liver damage and mitochondrial dysfunction. Mechanistically, SLC25A47 depletion leads to impaired hepatic pyruvate flux and malate accumulation in the mitochondria, thereby restricting hepatic gluconeogenesis. Together, the present study identified a crucial node in the liver mitochondria that regulates fasting-induced gluconeogenesis and energy homeostasis.
Collapse
Affiliation(s)
- Jin-Seon Yook
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA02115
| | - Zachary H. Taxin
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA02115
| | - Bo Yuan
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, MA02115
| | - Satoshi Oikawa
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA02115
| | - Christopher Auger
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA02115
| | - Beste Mutlu
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA02115
| | - Pere Puigserver
- Department of Cell Biology, Harvard Medical School, Boston, MA02115
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA02115
| | - Sheng Hui
- Department of Molecular Metabolism, Harvard T. H. Chan School of Public Health, Boston, MA02115
| | - Shingo Kajimura
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA02115
- HHMI, Chevy Chase, MD20815
| |
Collapse
|
11
|
Nelson C, Schmidt AB, Adelabu I, Nantogma S, Kiselev VG, Abdurraheem A, de Maissin H, Lehmkuhl S, Appelt S, Theis T, Chekmenev EY. Parahydrogen-Induced Carbon-13 Radiofrequency Amplification by Stimulated Emission of Radiation. Angew Chem Int Ed Engl 2023; 62:e202215678. [PMID: 36437237 PMCID: PMC9889133 DOI: 10.1002/anie.202215678] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022]
Abstract
The feasibility of Carbon-13 Radiofrequency (RF) Amplification by Stimulated Emission of Radiation (C-13 RASER) is demonstrated on a bolus of liquid hyperpolarized ethyl [1-13 C]acetate. Hyperpolarized ethyl [1-13 C]acetate was prepared via pairwise addition of parahydrogen to vinyl [1-13 C]acetate and polarization transfer from nascent parahydrogen-derived protons to the carbon-13 nucleus via magnetic field cycling yielding C-13 nuclear spin polarization of approximately 6 %. RASER signals were detected from samples with concentration ranging from 0.12 to 1 M concentration using a non-cryogenic 1.4T NMR spectrometer equipped with a radio-frequency detection coil with a quality factor (Q) of 32 without any modifications. C-13 RASER signals were observed for several minutes on a single bolus of hyperpolarized substrate to achieve 21 mHz NMR linewidths. The feasibility of creating long-lasting C-13 RASER on biomolecular carriers opens a wide range of new opportunities for the rapidly expanding field of C-13 magnetic resonance hyperpolarization.
Collapse
Affiliation(s)
- Christopher Nelson
- Department of Chemistry, North Carolina State University, 27695-8204, Raleigh, NC, USA
| | - Andreas B Schmidt
- Division of Medical Physics, Department of Radiology, Medical Center, Faculty of Medicine, University of Freiburg, Killianstr. 5a, 79106, Freiburg, Germany
- German Cancer Consortium (DKTK), partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, 48202, Detroit, MI, USA
| | - Isaiah Adelabu
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, 48202, Detroit, MI, USA
| | - Shiraz Nantogma
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, 48202, Detroit, MI, USA
| | - Valerij G Kiselev
- Division of Medical Physics, Department of Radiology, Medical Center, Faculty of Medicine, University of Freiburg, Killianstr. 5a, 79106, Freiburg, Germany
- German Cancer Consortium (DKTK), partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Abubakar Abdurraheem
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, 48202, Detroit, MI, USA
| | - Henri de Maissin
- Division of Medical Physics, Department of Radiology, Medical Center, Faculty of Medicine, University of Freiburg, Killianstr. 5a, 79106, Freiburg, Germany
- German Cancer Consortium (DKTK), partner site Freiburg and German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Sören Lehmkuhl
- Institute of Microstructure Technology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, 76344, Karlsruhe, Germany
| | - Stephan Appelt
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, 52056, Aachen, Germany
- Central Institute for Engineering, Electronics and Analytics-, Electronic Systems (ZEA-2), Forschungszentrum Jülich GmbH, 52425, Jülich, Germany
| | - Thomas Theis
- Department of Chemistry, North Carolina State University, 27695-8204, Raleigh, NC, USA
| | - Eduard Y Chekmenev
- Department of Chemistry, Integrative Biosciences (Ibio), Karmanos Cancer Institute (KCI), Wayne State University, 48202, Detroit, MI, USA
- Russian Academy of Sciences (RAS), 14 Leninskiy Prospekt, 119991, Moscow, Russia
| |
Collapse
|
12
|
Magnetic Resonance Imaging and Spectroscopy Methods to Study Hepatic Glucose Metabolism and Their Applications in the Healthy and Diabetic Liver. Metabolites 2022; 12:metabo12121223. [PMID: 36557261 PMCID: PMC9788351 DOI: 10.3390/metabo12121223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
The liver plays an important role in whole-body glucose homeostasis by taking up glucose from and releasing glucose into the blood circulation. In the postprandial state, excess glucose in the blood circulation is stored in hepatocytes as glycogen. In the postabsorptive state, the liver produces glucose by breaking down glycogen and from noncarbohydrate precursors such as lactate. In metabolic diseases such as diabetes, these processes are dysregulated, resulting in abnormal blood glucose levels. Magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) are noninvasive techniques that give unique insight into different aspects of glucose metabolism, such as glycogenesis, glycogenolysis, and gluconeogenesis, in the liver in vivo. Using these techniques, liver glucose metabolism has been studied in regard to a variety of interventions, such as fasting, meal intake, and exercise. Moreover, deviations from normal hepatic glucose metabolism have been investigated in both patients with type 1 and 2 diabetes, as well as the effects of antidiabetic medications. This review provides an overview of current MR techniques to measure hepatic glucose metabolism and the insights obtained by the application of these techniques in the healthy and diabetic liver.
Collapse
|
13
|
Lesner NP, Wang X, Chen Z, Frank A, Menezes CJ, House S, Shelton SD, Lemoff A, McFadden DG, Wansapura J, DeBerardinis RJ, Mishra P. Differential requirements for mitochondrial electron transport chain components in the adult murine liver. eLife 2022; 11:e80919. [PMID: 36154948 PMCID: PMC9648974 DOI: 10.7554/elife.80919] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/23/2022] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial electron transport chain (ETC) dysfunction due to mutations in the nuclear or mitochondrial genome is a common cause of metabolic disease in humans and displays striking tissue specificity depending on the affected gene. The mechanisms underlying tissue-specific phenotypes are not understood. Complex I (cI) is classically considered the entry point for electrons into the ETC, and in vitro experiments indicate that cI is required for basal respiration and maintenance of the NAD+/NADH ratio, an indicator of cellular redox status. This finding has largely not been tested in vivo. Here, we report that mitochondrial complex I is dispensable for homeostasis of the adult mouse liver; animals with hepatocyte-specific loss of cI function display no overt phenotypes or signs of liver damage, and maintain liver function, redox and oxygen status. Further analysis of cI-deficient livers did not reveal significant proteomic or metabolic changes, indicating little to no compensation is required in the setting of complex I loss. In contrast, complex IV (cIV) dysfunction in adult hepatocytes results in decreased liver function, impaired oxygen handling, steatosis, and liver damage, accompanied by significant metabolomic and proteomic perturbations. Our results support a model whereby complex I loss is tolerated in the mouse liver because hepatocytes use alternative electron donors to fuel the mitochondrial ETC.
Collapse
Affiliation(s)
- Nicholas P Lesner
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Xun Wang
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Zhenkang Chen
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Anderson Frank
- Department of Biochemistry, University of Texas Southwestern Medical CenterDallasUnited States
| | - Cameron J Menezes
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Sara House
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Spencer D Shelton
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Andrew Lemoff
- Department of Biochemistry, University of Texas Southwestern Medical CenterDallasUnited States
| | - David G McFadden
- Department of Biochemistry, University of Texas Southwestern Medical CenterDallasUnited States
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical CenterDallasUnited States
| | - Janaka Wansapura
- Advanced Imaging Research Center, University of Texas Southwestern Medical CenterDallasUnited States
| | - Ralph J DeBerardinis
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Pediatrics, University of Texas Southwestern Medical CenterDallasUnited States
- Howard Hughes Medical Institute, University of Texas Southwestern Medical CenterDallasUnited States
| | - Prashant Mishra
- Children's Medical Center Research Institute, University of Texas Southwestern Medical CenterDallasUnited States
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical CenterDallasUnited States
- Department of Pediatrics, University of Texas Southwestern Medical CenterDallasUnited States
| |
Collapse
|
14
|
Hsieh CY, Sung CH, Shen YL(E, Lai YC, Lu KY, Lin G. Developing a Method to Estimate the Downstream Metabolite Signals from Hyperpolarized [1- 13C]Pyruvate. SENSORS (BASEL, SWITZERLAND) 2022; 22:5480. [PMID: 35897987 PMCID: PMC9332172 DOI: 10.3390/s22155480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/18/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
Hyperpolarized carbon-13 MRI has the advantage of allowing the study of glycolytic flow in vivo or in vitro dynamically in real-time. The apparent exchange rate constant of a metabolite dynamic signal reflects the metabolite changes of a disease. Downstream metabolites can have a low signal-to-noise ratio (SNR), causing apparent exchange rate constant inconsistencies. Thus, we developed a method that estimates a more accurate metabolite signal. This method utilizes a kinetic model and background noise to estimate metabolite signals. Simulations and in vitro studies with photon-irradiated and control groups were used to evaluate the procedure. Simulated and in vitro exchange rate constants estimated using our method were compared with the raw signal values. In vitro data were also compared to the Area-Under-Curve (AUC) of the cell medium in 13C Nuclear Magnetic Resonance (NMR). In the simulations and in vitro experiments, our technique minimized metabolite signal fluctuations and maintained reliable apparent exchange rate constants. In addition, the apparent exchange rate constants of the metabolites showed differences between the irradiation and control groups after using our method. Comparing the in vitro results obtained using our method and NMR, both solutions showed consistency when uncertainty was considered, demonstrating that our method can accurately measure metabolite signals and show how glycolytic flow changes. The method enhanced the signals of the metabolites and clarified the metabolic phenotyping of tumor cells, which could benefit personalized health care and patient stratification in the future.
Collapse
Affiliation(s)
- Ching-Yi Hsieh
- Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University, Taoyuan 333, Taiwan; (C.-Y.H.); (C.-H.S.)
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan;
| | - Cheng-Hsuan Sung
- Medical Imaging Research Center, Institute for Radiological Research, Chang Gung University, Taoyuan 333, Taiwan; (C.-Y.H.); (C.-H.S.)
| | - Yi-Liang (Eric) Shen
- Department of Radiation Oncology and Proton Therapy Center, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan;
| | - Ying-Chieh Lai
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan;
| | - Kuan-Ying Lu
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan;
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan;
| | - Gigin Lin
- Clinical Metabolomics Core Laboratory, Chang Gung Memorial Hospital at Linkou, Taoyuan 333, Taiwan;
- Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan 333, Taiwan;
| |
Collapse
|
15
|
Yiew NKH, Finck BN. The mitochondrial pyruvate carrier at the crossroads of intermediary metabolism. Am J Physiol Endocrinol Metab 2022; 323:E33-E52. [PMID: 35635330 PMCID: PMC9273276 DOI: 10.1152/ajpendo.00074.2022] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Revised: 05/04/2022] [Accepted: 05/18/2022] [Indexed: 11/22/2022]
Abstract
Pyruvate metabolism, a central nexus of carbon homeostasis, is an evolutionarily conserved process and aberrant pyruvate metabolism is associated with and contributes to numerous human metabolic disorders including diabetes, cancer, and heart disease. As a product of glycolysis, pyruvate is primarily generated in the cytosol before being transported into the mitochondrion for further metabolism. Pyruvate entry into the mitochondrial matrix is a critical step for efficient generation of reducing equivalents and ATP and for the biosynthesis of glucose, fatty acids, and amino acids from pyruvate. However, for many years, the identity of the carrier protein(s) that transported pyruvate into the mitochondrial matrix remained a mystery. In 2012, the molecular-genetic identification of the mitochondrial pyruvate carrier (MPC), a heterodimeric complex composed of protein subunits MPC1 and MPC2, enabled studies that shed light on the many metabolic and physiological processes regulated by pyruvate metabolism. A better understanding of the mechanisms regulating pyruvate transport and the processes affected by pyruvate metabolism may enable novel therapeutics to modulate mitochondrial pyruvate flux to treat a variety of disorders. Herein, we review our current knowledge of the MPC, discuss recent advances in the understanding of mitochondrial pyruvate metabolism in various tissue and cell types, and address some of the outstanding questions relevant to this field.
Collapse
Affiliation(s)
- Nicole K H Yiew
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri
| | - Brian N Finck
- Center for Human Nutrition, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
16
|
Dong W, Rawat ES, Stephanopoulos G, Abu-Remaileh M. Isotope tracing in health and disease. Curr Opin Biotechnol 2022; 76:102739. [PMID: 35738210 PMCID: PMC9555185 DOI: 10.1016/j.copbio.2022.102739] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 04/16/2022] [Accepted: 04/27/2022] [Indexed: 11/16/2022]
Abstract
Biochemical characterization of metabolism provides molecular insights for understanding biology in health and disease. Over the past decades, metabolic perturbations have been implicated in cancer, neurodegeneration, and diabetes, among others. Isotope tracing is a technique that allows tracking of labeled atoms within metabolites through biochemical reactions. This technique has become an integral component of the contemporary metabolic research. Isotope tracing measures substrate contribution to downstream metabolites and indicates its utilization in cellular metabolic networks. In addition, isotopic labeling data are necessary for quantitative metabolic flux analysis. Here, we review recent work utilizing metabolic tracing to study health and disease, and highlight its application to interrogate subcellular, intercellular, and in vivo metabolism. We further discuss the current challenges and opportunities to expand the utility of isotope tracing to new research areas.
Collapse
Affiliation(s)
- Wentao Dong
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA 94305, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Eshaan S Rawat
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA 94305, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Gregory Stephanopoulos
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
| | - Monther Abu-Remaileh
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA; The Institute for Chemistry, Engineering & Medicine for Human Health (ChEM-H), Stanford University, Stanford, CA 94305, USA; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA.
| |
Collapse
|
17
|
Lee H, Xu Y, Zhu X, Jang C, Choi W, Bae H, Wang W, He L, Jin S, Arany Z, Simons M. Endothelium-derived lactate is required for pericyte function and blood-brain barrier maintenance. EMBO J 2022; 41:e109890. [PMID: 35243676 PMCID: PMC9058541 DOI: 10.15252/embj.2021109890] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 01/05/2023] Open
Abstract
Endothelial cells differ from other cell types responsible for the formation of the vascular wall in their unusual reliance on glycolysis for most energy needs, which results in extensive production of lactate. We find that endothelium-derived lactate is taken up by pericytes, and contributes substantially to pericyte metabolism including energy generation and amino acid biosynthesis. Endothelial-pericyte proximity is required to facilitate the transport of endothelium-derived lactate into pericytes. Inhibition of lactate production in the endothelium by deletion of the glucose transporter-1 (GLUT1) in mice results in loss of pericyte coverage in the retina and brain vasculatures, leading to the blood-brain barrier breakdown and increased permeability. These abnormalities can be largely restored by oral lactate administration. Our studies demonstrate an unexpected link between endothelial and pericyte metabolisms and the role of endothelial lactate production in the maintenance of the blood-brain barrier integrity. In addition, our observations indicate that lactate supplementation could be a useful therapeutic approach for GLUT1 deficiency metabolic syndrome patients.
Collapse
Affiliation(s)
- Heon‐Woo Lee
- Yale Cardiovascular Research CenterSection of Cardiovascular MedicineDepartment of Internal MedicineYale University School of MedicineNew HavenCTUSA
| | - Yanying Xu
- Yale Cardiovascular Research CenterSection of Cardiovascular MedicineDepartment of Internal MedicineYale University School of MedicineNew HavenCTUSA
- Department of Cardiovascular MedicineXiangya HospitalCentral South UniversityChangshaChina
| | - Xiaolong Zhu
- Yale Cardiovascular Research CenterSection of Cardiovascular MedicineDepartment of Internal MedicineYale University School of MedicineNew HavenCTUSA
| | - Cholsoon Jang
- Department of Biological ChemistryUniversity of California IrvineIrvineCAUSA
| | - Woosoung Choi
- School of Life Sciences and Cell Logistics Research CenterGwangju Institute of Science and Technology (GIST)GwangjuKorea
| | - Hosung Bae
- Department of Biological ChemistryUniversity of California IrvineIrvineCAUSA
| | - Weiwei Wang
- W. M. Keck Biotechnology Resource LaboratoryYale University School of MedicineNew HavenCTUSA
| | - Liqun He
- Department of Immunology, Genetics and PathologyRudbeck LaboratoryUppsala UniversityUppsalaSweden
| | - Suk‐Won Jin
- Yale Cardiovascular Research CenterSection of Cardiovascular MedicineDepartment of Internal MedicineYale University School of MedicineNew HavenCTUSA
- School of Life Sciences and Cell Logistics Research CenterGwangju Institute of Science and Technology (GIST)GwangjuKorea
| | - Zoltan Arany
- Cardiovascular InstitutePerelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA
| | - Michael Simons
- Yale Cardiovascular Research CenterSection of Cardiovascular MedicineDepartment of Internal MedicineYale University School of MedicineNew HavenCTUSA
- Department of Cell BiologyYale University School of MedicineNew HavenCTUSA
| |
Collapse
|
18
|
Giacalone AG, Merritt ME, Ragavan M. Ex Vivo Hepatic Perfusion Through the Portal Vein in Mouse. J Vis Exp 2022:10.3791/63154. [PMID: 35343950 PMCID: PMC9258001 DOI: 10.3791/63154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Metabolic diseases such as diabetes, pre-diabetes, non-alcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH) are becoming increasingly common. Ex vivo liver perfusions allow for a comprehensive analysis of liver metabolism using nuclear magnetic resonance (NMR), in nutritional conditions that can be rigorously controlled. As in silico simulations remain a primarily theoretical means of assessing hormone actions and the effects of pharmaceutical intervention, the perfused liver remains one of the most valuable test beds for understanding hepatic metabolism. As these studies guide basic insights into hepatic physiology, results must be accurate and reproducible. The greatest factor in the reproducibility of ex vivo hepatic perfusion is the quality of surgery. Therefore, we have introduced an organized and streamlined method to perform ex vivo mouse liver perfusions in the context of in situ NMR experiments. We also describe a unique application and discuss common issues encountered in these studies. The overall purpose is to provide an uncomplicated guide to a technique we have refined over several years that we deem the golden standard for obtaining reproducible results in hepatic resections and perfusions in the context of in situ NMR experiments. The distance to the center of the field for the magnet as well as the inaccessibility of the tissue to intervention during the NMR experiment makes our methods novel.
Collapse
Affiliation(s)
| | - Matthew E Merritt
- Department of Biochemistry and Molecular Biology, University of Florida
| | - Mukundan Ragavan
- Department of Biochemistry and Molecular Biology, University of Florida;
| |
Collapse
|
19
|
Ma J, Pinho MC, Harrison CE, Chen J, Sun C, Hackett EP, Liticker J, Ratnakar J, Reed GD, Chen AP, Sherry AD, Malloy CR, Wright SM, Madden CJ, Park JM. Dynamic 13 C MR spectroscopy as an alternative to imaging for assessing cerebral metabolism using hyperpolarized pyruvate in humans. Magn Reson Med 2022; 87:1136-1149. [PMID: 34687086 PMCID: PMC8776582 DOI: 10.1002/mrm.29049] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/01/2021] [Accepted: 09/29/2021] [Indexed: 11/10/2022]
Abstract
PURPOSE This study is to investigate time-resolved 13 C MR spectroscopy (MRS) as an alternative to imaging for assessing pyruvate metabolism using hyperpolarized (HP) [1-13 C]pyruvate in the human brain. METHODS Time-resolved 13 C spectra were acquired from four axial brain slices of healthy human participants (n = 4) after a bolus injection of HP [1-13 C]pyruvate. 13 C MRS with low flip-angle excitations and a multichannel 13 C/1 H dual-frequency radiofrequency (RF) coil were exploited for reliable and unperturbed assessment of HP pyruvate metabolism. Slice-wise areas under the curve (AUCs) of 13 C-metabolites were measured and kinetic analysis was performed to estimate the production rates of lactate and HCO3- . Linear regression analysis between brain volumes and HP signals was performed. Region-focused pyruvate metabolism was estimated using coil-wise 13 C reconstruction. Reproducibility of HP pyruvate exams was presented by performing two consecutive injections with a 45-minutes interval. RESULTS [1-13 C]Lactate relative to the total 13 C signal (tC) was 0.21-0.24 in all slices. [13 C] HCO3- /tC was 0.065-0.091. Apparent conversion rate constants from pyruvate to lactate and HCO3- were calculated as 0.014-0.018 s-1 and 0.0043-0.0056 s-1 , respectively. Pyruvate/tC and lactate/tC were in moderate linear relationships with fractional gray matter volume within each slice. White matter presented poor linear regression fit with HP signals, and moderate correlations of the fractional cerebrospinal fluid volume with pyruvate/tC and lactate/tC were measured. Measured HP signals were comparable between two consecutive exams with HP [1-13 C]pyruvate. CONCLUSIONS Dynamic MRS in combination with multichannel RF coils is an affordable and reliable alternative to imaging methods in investigating cerebral metabolism using HP [1-13 C]pyruvate.
Collapse
Affiliation(s)
- Junjie Ma
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Marco C. Pinho
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Crystal E. Harrison
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jun Chen
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chenhao Sun
- Department of Electrical and Computer Engineering, Texas A & M, College Station, TX, USA
| | - Edward P. Hackett
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jeff Liticker
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - James Ratnakar
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | | | | | - A. Dean Sherry
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Biochemistry and Chemical Biology, University of Texas Dallas, Richardson, TX, USA
| | - Craig R. Malloy
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Steven M. Wright
- Department of Electrical and Computer Engineering, Texas A & M, College Station, TX, USA
| | - Christopher J. Madden
- Department of Neurological Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jae Mo Park
- Advanced Imaging Research Center, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Radiology, University of Texas Southwestern Medical Center, Dallas, TX, USA,Department of Electrical and Computer Engineering, University of Texas Dallas, Richardson, TX, USA,Correspondence to: Jae Mo Park, Ph.D., 5323 Harry Hines Blvd. Dallas, Texas 75390-8568, , Tel: +1-214-645-7206, Fax: +1-214-645-2744
| |
Collapse
|
20
|
Ragavan M, McLeod MA, Rushin A, Merritt ME. Detecting de novo Hepatic Ketogenesis Using Hyperpolarized [2- 13C] Pyruvate. Front Physiol 2022; 13:832403. [PMID: 35197867 PMCID: PMC8859440 DOI: 10.3389/fphys.2022.832403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/14/2022] [Indexed: 11/28/2022] Open
Abstract
The role of ketones in metabolic health has progressed over the past two decades, moving from what was perceived as a simple byproduct of fatty acid oxidation to a central player in a multiplicity of disease states. Previous work with hyperpolarized (HP) 13C has shown that ketone production can be detected when using precursors that labeled acetyl-CoA at the C1 position, often in tissues that are not normally recognized as ketogenic. Here, we assay metabolism of HP [2-13C]pyruvate in the perfused mouse liver, a classic metabolic testbed where nutritional conditions can be precisely controlled. Livers perfused with long-chain fatty acids or the medium-chain fatty acid octanoate showed no evidence of ketogenesis in the 13C spectrum. In contrast, addition of dichloroacetate, a potent inhibitor of pyruvate dehydrogenase kinase, resulted in significant production of both acetoacetate and 3-hydroxybutyrate from the pyruvate precursor. This result indicates that ketones are readily produced from carbohydrates, but only in the case where pyruvate dehydrogenase activity is upregulated.
Collapse
Affiliation(s)
| | | | | | - Matthew E. Merritt
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL, United States
| |
Collapse
|
21
|
Can E, Bastiaansen JAM, Couturier DL, Gruetter R, Yoshihara HAI, Comment A. [ 13C]bicarbonate labelled from hyperpolarized [1- 13C]pyruvate is an in vivo marker of hepatic gluconeogenesis in fasted state. Commun Biol 2022; 5:10. [PMID: 35013537 PMCID: PMC8748681 DOI: 10.1038/s42003-021-02978-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 12/07/2021] [Indexed: 01/07/2023] Open
Abstract
Hyperpolarized [1-13C]pyruvate enables direct in vivo assessment of real-time liver enzymatic activities by 13C magnetic resonance. However, the technique usually requires the injection of a highly supraphysiological dose of pyruvate. We herein demonstrate that liver metabolism can be measured in vivo with hyperpolarized [1-13C]pyruvate administered at two- to three-fold the basal plasma concentration. The flux through pyruvate dehydrogenase, assessed by 13C-labeling of bicarbonate in the fed condition, was found to be saturated or partially inhibited by supraphysiological doses of hyperpolarized [1-13C]pyruvate. The [13C]bicarbonate signal detected in the liver of fasted rats nearly vanished after treatment with a phosphoenolpyruvate carboxykinase (PEPCK) inhibitor, indicating that the signal originates from the flux through PEPCK. In addition, the normalized [13C]bicarbonate signal in fasted untreated animals is dose independent across a 10-fold range, highlighting that PEPCK and pyruvate carboxylase are not saturated and that hepatic gluconeogenesis can be directly probed in vivo with hyperpolarized [1-13C]pyruvate. Can et al. demonstrate the ability to use hyperpolarized [1-13C]pyruvate at nearphysiological concentrations to directly assess liver enzymatic activities by 13C magnetic resonance. While in the fed state, the normalized [13C]bicarbonate signal produced from hyperpolarized [1-13C]pyruvate derives from PDH activity, which is saturated at supraphysiological doses, it results from PEPCK in the fasted state and is dose-independent, allowing non-invasive in vivo detection of hepatic gluconeogenesis.”
Collapse
Affiliation(s)
- Emine Can
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Jessica A M Bastiaansen
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland.,Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
| | | | - Rolf Gruetter
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Hikari A I Yoshihara
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland
| | - Arnaud Comment
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, Cambridgeshire, CB2 0RE, UK. .,General Electric Healthcare, Chalfont St Giles, Buckinghamshire, HP8 4SP, UK.
| |
Collapse
|
22
|
Yoshihara HAI, Comment A, Schwitter J. Assessment of Aspartate and Bicarbonate Produced From Hyperpolarized [1- 13C]Pyruvate as Markers of Renal Gluconeogenesis. Front Physiol 2021; 12:792769. [PMID: 34955898 PMCID: PMC8702956 DOI: 10.3389/fphys.2021.792769] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/18/2021] [Indexed: 11/13/2022] Open
Abstract
As both a consumer and producer of glucose, the kidney plays a significant role in glucose homeostasis. Measuring renal gluconeogenesis requires invasive techniques, and less invasive methods would allow renal gluconeogenesis to be measured more routinely. Magnetic resonance spectroscopy and imaging of infused substrates bearing hyperpolarized carbon-13 spin labels allows metabolism to be detected within the body with excellent sensitivity. Conversion of hyperpolarized 1-13C pyruvate in the fasted rat liver is associated with gluconeogenic flux through phosphoenolpyruvate carboxykinase (PEPCK) rather than pyruvate dehydrogenase (PDH), and this study tested whether this was also the case in the kidney. The left kidney was scanned in fed and overnight-fasted rats either with or without prior treatment by the PEPCK inhibitor 3-mercaptopicolinic acid (3-MPA) following infusion of hyperpolarized 1-13C pyruvate. The 13C-bicarbonate signal normalized to the total metabolite signal was 3.2-fold lower in fasted rats (p = 0.00073) and was not significantly affected by 3-MPA treatment in either nutritional state. By contrast, the normalized [1-13C]aspartate signal was on average 2.2-fold higher in the fasted state (p = 0.038), and following 3-MPA treatment it was 2.8-fold lower in fed rats and 15-fold lower in fasted rats (p = 0.001). These results confirm that, unlike in the liver, most of the pyruvate-to-bicarbonate conversion in the fasted kidney results from PDH flux. The higher conversion to aspartate in fasted kidney and the marked drop following PEPCK inhibition demonstrate the potential of this metabolite as a marker of renal gluconeogenesis.
Collapse
Affiliation(s)
- Hikari A. I. Yoshihara
- Laboratory for Functional and Metabolic Imaging, Institute of Physics, Swiss Federal Institute of Technology (EPFL), Lausanne, Switzerland
| | - Arnaud Comment
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, United Kingdom
- General Electric Healthcare, Chalfont St Giles, United Kingdom
| | - Juerg Schwitter
- Division of Cardiology, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Cardiac MR Center, Lausanne University Hospital (CHUV), University of Lausanne (UNIL), Lausanne, Switzerland
| |
Collapse
|
23
|
Yang Q, Liu J, Wang Y, Zhao W, Wang W, Cui J, Yang J, Yue Y, Zhang S, Chu M, Lyu Q, Ma L, Tang Y, Hu Y, Miao K, Zhao H, Tian J, An L. A proteomic atlas of ligand-receptor interactions at the ovine maternal-fetal interface reveals the role of histone lactylation in uterine remodeling. J Biol Chem 2021; 298:101456. [PMID: 34861240 PMCID: PMC8733267 DOI: 10.1016/j.jbc.2021.101456] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 02/05/2023] Open
Abstract
Well-orchestrated maternal–fetal cross talk occurs via secreted ligands, interacting receptors, and coupled intracellular pathways between the conceptus and endometrium and is essential for successful embryo implantation. However, previous studies mostly focus on either the conceptus or the endometrium in isolation. The lack of integrated analysis impedes our understanding of early maternal–fetal cross talk. Herein, focusing on ligand–receptor complexes and coupled pathways at the maternal–fetal interface in sheep, we provide the first comprehensive proteomic map of ligand–receptor pathway cascades essential for embryo implantation. We demonstrate that these cascades are associated with cell adhesion and invasion, redox homeostasis, and the immune response. Candidate interactions and their physiological roles were further validated by functional experiments. We reveal the physical interaction of albumin and claudin 4 and their roles in facilitating embryo attachment to endometrium. We also demonstrate a novel function of enhanced conceptus glycolysis in remodeling uterine receptivity by inducing endometrial histone lactylation, a newly identified histone modification. Results from in vitro and in vivo models supported the essential role of lactate in inducing endometrial H3K18 lactylation and in regulating redox homeostasis and apoptotic balance to ensure successful implantation. By reconstructing a map of potential ligand–receptor pathway cascades at the maternal–fetal interface, our study presents new concepts for understanding molecular and cellular mechanisms that fine-tune conceptus–endometrium cross talk during implantation. This provides more direct and accurate insights for developing potential clinical intervention strategies to improve pregnancy outcomes following both natural and assisted conception.
Collapse
Affiliation(s)
- Qianying Yang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Juan Liu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yue Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Wei Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Wenjing Wang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jian Cui
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jiajun Yang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yuan Yue
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Shuai Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Meiqiang Chu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Qingji Lyu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Lizhu Ma
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yawen Tang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yupei Hu
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Kai Miao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Haichao Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Jianhui Tian
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Lei An
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
| |
Collapse
|
24
|
Lima VF, Erban A, Daubermann AG, Freire FBS, Porto NP, Cândido-Sobrinho SA, Medeiros DB, Schwarzländer M, Fernie AR, Dos Anjos L, Kopka J, Daloso DM. Establishment of a GC-MS-based 13 C-positional isotopomer approach suitable for investigating metabolic fluxes in plant primary metabolism. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:1213-1233. [PMID: 34486764 DOI: 10.1111/tpj.15484] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/20/2021] [Accepted: 08/30/2021] [Indexed: 06/13/2023]
Abstract
13 C-Metabolic flux analysis (13 C-MFA) has greatly contributed to our understanding of plant metabolic regulation. However, the generation of detailed in vivo flux maps remains a major challenge. Flux investigations based on nuclear magnetic resonance have resolved small networks with high accuracy. Mass spectrometry (MS) approaches have broader potential, but have hitherto been limited in their power to deduce flux information due to lack of atomic level position information. Herein we established a gas chromatography (GC) coupled to MS-based approach that provides 13 C-positional labelling information in glucose, malate and glutamate (Glu). A map of electron impact (EI)-mediated MS fragmentation was created and validated by 13 C-positionally labelled references via GC-EI-MS and GC-atmospheric pressure chemical ionization-MS technologies. The power of the approach was revealed by analysing previous 13 C-MFA data from leaves and guard cells, and 13 C-HCO3 labelling of guard cells harvested in the dark and after the dark-to-light transition. We demonstrated that the approach is applicable to established GC-EI-MS-based 13 C-MFA without the need for experimental adjustment, but will benefit in the future from paired analyses by the two GC-MS platforms. We identified specific glucose carbon atoms that are preferentially labelled by photosynthesis and gluconeogenesis, and provide an approach to investigate the phosphoenolpyruvate carboxylase (PEPc)-derived 13 C-incorporation into malate and Glu. Our results suggest that gluconeogenesis and the PEPc-mediated CO2 assimilation into malate are activated in a light-independent manner in guard cells. We further highlight that the fluxes from glycolysis and PEPc toward Glu are restricted by the mitochondrial thioredoxin system in illuminated leaves.
Collapse
Affiliation(s)
- Valéria F Lima
- LabPLant, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza-CE, 60451-970, Brazil
| | - Alexander Erban
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, D-14476, Germany
| | - André G Daubermann
- Departamento de Biologia, Setor de Fisiologia Vegetal, Universidade Federal de Lavras, Lavras-MG, 37200-900, Brazil
| | - Francisco Bruno S Freire
- LabPLant, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza-CE, 60451-970, Brazil
| | - Nicole P Porto
- LabPLant, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza-CE, 60451-970, Brazil
| | - Silvio A Cândido-Sobrinho
- LabPLant, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza-CE, 60451-970, Brazil
| | - David B Medeiros
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, D-14476, Germany
| | - Markus Schwarzländer
- Institute of Plant Biology and Biotechnology, Westfälische-Wilhelms-Universität Münster, Münster, D-48143, Germany
| | - Alisdair R Fernie
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, D-14476, Germany
| | - Leticia Dos Anjos
- Departamento de Biologia, Setor de Fisiologia Vegetal, Universidade Federal de Lavras, Lavras-MG, 37200-900, Brazil
| | - Joachim Kopka
- Max-Planck-Institute of Molecular Plant Physiology, Potsdam-Golm, D-14476, Germany
| | - Danilo M Daloso
- LabPLant, Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, Fortaleza-CE, 60451-970, Brazil
| |
Collapse
|
25
|
Singh J, Suh EH, Sharma G, Chen J, Hackett EP, Wen X, Sherry AD, Khemtong C, Malloy CR, Park JM, Kovacs Z. 13C-Labeled Diethyl Ketoglutarate Derivatives as Hyperpolarized Probes of 2-Ketoglutarate Dehydrogenase Activity. ANALYSIS & SENSING 2021; 1:156-160. [PMID: 35669533 PMCID: PMC9165698 DOI: 10.1002/anse.202100021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Indexed: 11/11/2022]
Abstract
The TCA cycle is a central metabolic pathway for energy production and biosynthesis. A major control point of metabolic flux through the cycle is the decarboxylation of 2-ketoglutarate by the TCA cycle enzyme 2-ketoglutarate dehydrogenase (2-KGDH). In this project, we developed 13C labeled 2-ketoglutarate derivatives to monitor 2-KGDH activity in vivo. 13C NMR analysis of liver extracts revealed that uniformly 13C labeled 2-ketogutarate, in its cell permeable ester form, was rapidly taken up and hydrolyzed in liver and underwent extensive metabolism to produce labeled glutamate, succinate, lactate and other metabolites. Diethyl [1,2-13C2]-2-ketoglutarate was successfully polarized by dynamic nuclear polarization and within seconds after injection into rats, the probe produced hyperpolarized [13C]bicarbonate in the liver reflecting flux through the TCA cycle. These experiments demonstrate that this tracer offers the possibility of directly monitoring flux through 2-KGDH in vivo.
Collapse
Affiliation(s)
- Jaspal Singh
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Eul Hyun Suh
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Gaurav Sharma
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Jun Chen
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Edward P Hackett
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Xiaodong Wen
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - A Dean Sherry
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Chalermchai Khemtong
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Florida, Gainesville, FL and Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL
| | - Craig R Malloy
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Jae Mo Park
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| | - Zoltan Kovacs
- Advanced Imaging Research Center, University of Texas South-western Medical Center, Dallas, TX
| |
Collapse
|
26
|
Non-Invasive Analysis of Human Liver Metabolism by Magnetic Resonance Spectroscopy. Metabolites 2021; 11:metabo11110751. [PMID: 34822409 PMCID: PMC8623827 DOI: 10.3390/metabo11110751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
The liver is a key node of whole-body nutrient and fuel metabolism and is also the principal site for detoxification of xenobiotic compounds. As such, hepatic metabolite concentrations and/or turnover rates inform on the status of both hepatic and systemic metabolic diseases as well as the disposition of medications. As a tool to better understand liver metabolism in these settings, in vivo magnetic resonance spectroscopy (MRS) offers a non-invasive means of monitoring hepatic metabolic activity in real time both by direct observation of concentrations and dynamics of specific metabolites as well as by observation of their enrichment by stable isotope tracers. This review summarizes the applications and advances in human liver metabolic studies by in vivo MRS over the past 35 years and discusses future directions and opportunities that will be opened by the development of ultra-high field MR systems and by hyperpolarized stable isotope tracers.
Collapse
|
27
|
Yako H, Niimi N, Kato A, Takaku S, Tatsumi Y, Nishito Y, Kato K, Sango K. Role of pyruvate in maintaining cell viability and energy production under high-glucose conditions. Sci Rep 2021; 11:18910. [PMID: 34556698 PMCID: PMC8460646 DOI: 10.1038/s41598-021-98082-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 09/03/2021] [Indexed: 11/25/2022] Open
Abstract
Pyruvate functions as a key molecule in energy production and as an antioxidant. The efficacy of pyruvate supplementation in diabetic retinopathy and nephropathy has been shown in animal models; however, its significance in the functional maintenance of neurons and Schwann cells under diabetic conditions remains unknown. We observed rapid and extensive cell death under high-glucose (> 10 mM) and pyruvate-starved conditions. Exposure of Schwann cells to these conditions led to a significant decrease in glycolytic flux, mitochondrial respiration and ATP production, accompanied by enhanced collateral glycolysis pathways (e.g., polyol pathway). Cell death could be prevented by supplementation with 2-oxoglutarate (a TCA cycle intermediate), benfotiamine (the vitamin B1 derivative that suppresses the collateral pathways), or the poly (ADP-ribose) polymerase (PARP) inhibitor, rucaparib. Our findings suggest that exogenous pyruvate plays a pivotal role in maintaining glycolysis–TCA cycle flux and ATP production under high-glucose conditions by suppressing PARP activity.
Collapse
Affiliation(s)
- Hideji Yako
- Diabetic Neuropathy Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan.
| | - Naoko Niimi
- Diabetic Neuropathy Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
| | - Ayako Kato
- Laboratory of Medicine, Aichi Gakuin University, School of Pharmacy, Nagoya, Japan
| | - Shizuka Takaku
- Diabetic Neuropathy Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan
| | - Yasuaki Tatsumi
- Laboratory of Medicine, Aichi Gakuin University, School of Pharmacy, Nagoya, Japan
| | - Yasumasa Nishito
- Basic Technology Research Center, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Koichi Kato
- Laboratory of Medicine, Aichi Gakuin University, School of Pharmacy, Nagoya, Japan
| | - Kazunori Sango
- Diabetic Neuropathy Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 156-8506, Japan.
| |
Collapse
|
28
|
Ragavan M, McLeod MA, Giacalone AG, Merritt ME. Hyperpolarized Dihydroxyacetone Is a Sensitive Probe of Hepatic Gluconeogenic State. Metabolites 2021; 11:441. [PMID: 34357335 PMCID: PMC8307483 DOI: 10.3390/metabo11070441] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/23/2021] [Accepted: 07/01/2021] [Indexed: 11/25/2022] Open
Abstract
Type II diabetes and pre-diabetes are widely prevalent among adults. Elevated serum glucose levels are commonly treated by targeting hepatic gluconeogenesis for downregulation. However, direct measurement of hepatic gluconeogenic capacity is accomplished only via tracer metabolism approaches that rely on multiple assumptions, and are clinically intractable due to expense and time needed for the studies. We previously introduced hyperpolarized (HP) [2-13C]dihydroxyacetone (DHA) as a sensitive detector of gluconeogenic potential, and showed that feeding and fasting produced robust changes in the ratio of detected hexoses (6C) to trioses (3C) in the perfused liver. To confirm that this ratio is robust in the setting of treatment and hormonal control, we used ex vivo perfused mouse livers from BLKS mice (glucagon treated and metformin treated), and db/db mice. We confirm that the ratio of signal intensities of 6C to 3C in 13C nuclear magnetic resonance spectra post HP DHA administration is sensitive to hepatic gluconeogenic state. This method is directly applicable in vivo and can be implemented with existing technologies without the need for substantial modifications.
Collapse
Affiliation(s)
| | | | | | - Matthew E. Merritt
- Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL 32610, USA; (M.R.); (M.A.M.); (A.G.G.)
| |
Collapse
|
29
|
Qiao K, Le Page LM, Chaumeil MM. Non-Invasive Differentiation of M1 and M2 Activation in Macrophages Using Hyperpolarized 13C MRS of Pyruvate and DHA at 1.47 Tesla. Metabolites 2021; 11:410. [PMID: 34206326 PMCID: PMC8305442 DOI: 10.3390/metabo11070410] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/16/2021] [Accepted: 06/17/2021] [Indexed: 01/09/2023] Open
Abstract
Macrophage activation, first generalized to the M1/M2 dichotomy, is a complex and central process of the innate immune response. Simply, M1 describes the classical proinflammatory activation, leading to tissue damage, and M2 the alternative activation promoting tissue repair. Given the central role of macrophages in multiple diseases, the ability to noninvasively differentiate between M1 and M2 activation states would be highly valuable for monitoring disease progression and therapeutic responses. Since M1/M2 activation patterns are associated with differential metabolic reprogramming, we hypothesized that hyperpolarized 13C magnetic resonance spectroscopy (HP 13C MRS), an innovative metabolic imaging approach, could distinguish between macrophage activation states noninvasively. The metabolic conversions of HP [1-13C]pyruvate to HP [1-13C]lactate, and HP [1-13C]dehydroascorbic acid to HP [1-13C]ascorbic acid were monitored in live M1 and M2 activated J774a.1 macrophages noninvasively by HP 13C MRS on a 1.47 Tesla NMR system. Our results show that both metabolic conversions were significantly increased in M1 macrophages compared to M2 and nonactivated cells. Biochemical assays and high resolution 1H MRS were also performed to investigate the underlying changes in enzymatic activities and metabolite levels linked to M1/M2 activation. Altogether, our results demonstrate the potential of HP 13C MRS for monitoring macrophage activation states noninvasively.
Collapse
Affiliation(s)
- Kai Qiao
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA 94143, USA; (K.Q.); (L.M.L.P.)
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| | - Lydia M. Le Page
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA 94143, USA; (K.Q.); (L.M.L.P.)
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| | - Myriam M. Chaumeil
- Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, CA 94143, USA; (K.Q.); (L.M.L.P.)
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA 94143, USA
| |
Collapse
|
30
|
Prochownik EV, Wang H. The Metabolic Fates of Pyruvate in Normal and Neoplastic Cells. Cells 2021; 10:cells10040762. [PMID: 33808495 PMCID: PMC8066905 DOI: 10.3390/cells10040762] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/23/2021] [Accepted: 03/28/2021] [Indexed: 02/06/2023] Open
Abstract
Pyruvate occupies a central metabolic node by virtue of its position at the crossroads of glycolysis and the tricarboxylic acid (TCA) cycle and its production and fate being governed by numerous cell-intrinsic and extrinsic factors. The former includes the cell’s type, redox state, ATP content, metabolic requirements and the activities of other metabolic pathways. The latter include the extracellular oxygen concentration, pH and nutrient levels, which are in turn governed by the vascular supply. Within this context, we discuss the six pathways that influence pyruvate content and utilization: 1. The lactate dehydrogenase pathway that either converts excess pyruvate to lactate or that regenerates pyruvate from lactate for use as a fuel or biosynthetic substrate; 2. The alanine pathway that generates alanine and other amino acids; 3. The pyruvate dehydrogenase complex pathway that provides acetyl-CoA, the TCA cycle’s initial substrate; 4. The pyruvate carboxylase reaction that anaplerotically supplies oxaloacetate; 5. The malic enzyme pathway that also links glycolysis and the TCA cycle and generates NADPH to support lipid bio-synthesis; and 6. The acetate bio-synthetic pathway that converts pyruvate directly to acetate. The review discusses the mechanisms controlling these pathways, how they cross-talk and how they cooperate and are regulated to maximize growth and achieve metabolic and energetic harmony.
Collapse
Affiliation(s)
- Edward V. Prochownik
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
- The Department of Microbiology and Molecular Genetics, UPMC, Pittsburgh, PA 15213, USA
- The Hillman Cancer Center, UPMC, Pittsburgh, PA 15213, USA
- The Pittsburgh Liver Research Center, Pittsburgh, PA 15260, USA
- Correspondence: ; Tel.: +1-(412)-692-6795
| | - Huabo Wang
- Division of Hematology/Oncology, UPMC Children’s Hospital of Pittsburgh, Pittsburgh, PA 15224, USA;
| |
Collapse
|
31
|
Saed CT, Tabatabaei Dakhili SA, Ussher JR. Pyruvate Dehydrogenase as a Therapeutic Target for Nonalcoholic Fatty Liver Disease. ACS Pharmacol Transl Sci 2021; 4:582-588. [PMID: 33860188 DOI: 10.1021/acsptsci.0c00208] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Indexed: 12/19/2022]
Abstract
Excess caloric intake combined with a sedentary lifestyle in the general population has greatly increased the prevalence of obesity and nonalcoholic fatty liver disease (NAFLD), which is defined as the accumulation of excess fat in the liver in the absence of alcohol abuse or other attributable causes such as infection with hepatitis C. Furthermore, NAFLD increases the risk for insulin resistance, type 2 diabetes (T2D), and cardiovascular disease, while currently having no approved therapy to counteract its pathology. Thus, increasing efforts to understand the mechanisms responsible for NAFLD have been pursued in preclinical studies, in the hopes of developing novel therapies that can prevent the progression of insulin resistance and/or T2D. The pathology of NAFLD is multifactorial, with proposed mechanisms including inflammation, oxidative stress, and mitochondrial dysfunction to name a few. The latter remains a subject of ongoing debate, but may be attributed to impaired hepatic fatty acid oxidation, thereby increasing the accumulation of triacylglycerol within hepatocytes. More recent studies have also demonstrated that the mitochondrial dysfunction in NAFLD may also encompass impairments in glucose oxidation, despite oxidative energy production having minimal contribution to overall glucose/pyruvate metabolism in the liver. Accordingly, strategies to reverse this defect in glucose oxidation can ameliorate hepatic steatosis and improve glucose homeostasis. We will review herein the evidence supporting impaired hepatic glucose oxidation as a mechanism of NAFLD, while discussing the validity of pyruvate dehydrogenase (PDH), the rate-limiting enzyme of glucose oxidation, as a potential target for NAFLD. In addition, we will discuss potential mechanisms of action by which increased hepatic PDH activity and subsequent glucose oxidation can reverse the pathology of obesity-induced NAFLD, as well as opportunities to target this pathway with clinical agents.
Collapse
Affiliation(s)
- Christina T Saed
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Seyed Amirhossein Tabatabaei Dakhili
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - John R Ussher
- Faculty of Pharmacy and Pharmaceutical Sciences, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.,Cardiovascular Research Centre, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| |
Collapse
|
32
|
Marco-Rius I, Wright AJ, Hu DE, Savic D, Miller JJ, Timm KN, Tyler D, Brindle KM, Comment A. Probing hepatic metabolism of [2- 13C]dihydroxyacetone in vivo with 1H-decoupled hyperpolarized 13C-MR. MAGMA (NEW YORK, N.Y.) 2021; 34:49-56. [PMID: 32910316 PMCID: PMC7910257 DOI: 10.1007/s10334-020-00884-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/07/2020] [Accepted: 08/27/2020] [Indexed: 01/06/2023]
Abstract
OBJECTIVES To enhance detection of the products of hyperpolarized [2-13C]dihydroxyacetone metabolism for assessment of three metabolic pathways in the liver in vivo. Hyperpolarized [2-13C]DHAc emerged as a promising substrate to follow gluconeogenesis, glycolysis and the glycerol pathways. However, the use of [2-13C]DHAc in vivo has not taken off because (i) the chemical shift range of [2-13C]DHAc and its metabolic products span over 144 ppm, and (ii) 1H decoupling is required to increase spectral resolution and sensitivity. While these issues are trivial for high-field vertical-bore NMR spectrometers, horizontal-bore small-animal MR scanners are seldom equipped for such experiments. METHODS Real-time hepatic metabolism of three fed mice was probed by 1H-decoupled 13C-MR following injection of hyperpolarized [2-13C]DHAc. The spectra of [2-13C]DHAc and its metabolic products were acquired in a 7 T small-animal MR scanner using three purpose-designed spectral-spatial radiofrequency pulses that excited a spatial bandwidth of 8 mm with varying spectral bandwidths and central frequencies (chemical shifts). RESULTS The metabolic products detected in vivo include glycerol 3-phosphate, glycerol, phosphoenolpyruvate, lactate, alanine, glyceraldehyde 3-phosphate and glucose 6-phosphate. The metabolite-to-substrate ratios were comparable to those reported previously in perfused liver. DISCUSSION Three metabolic pathways can be probed simultaneously in the mouse liver in vivo, in real time, using hyperpolarized DHAc.
Collapse
Affiliation(s)
- Irene Marco-Rius
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK.
- Institute for Bioengineering of Catalonia, Barcelona, Spain.
| | - Alan J Wright
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - De-En Hu
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Dragana Savic
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Division of Medicine, University of Oxford, Oxford, UK
| | - Jack J Miller
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Division of Medicine, University of Oxford, Oxford, UK
| | - Kerstin N Timm
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Damian Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Division of Medicine, University of Oxford, Oxford, UK
| | - Kevin M Brindle
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Arnaud Comment
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
- General Electric Healthcare, Chalfont St Giles, UK
| |
Collapse
|
33
|
Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance. SCI 2021. [DOI: 10.3390/sci3010008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a noninvasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects.
Collapse
|
34
|
Timm KN, Ball V, Miller JJ, Savic D, West JA, Griffin JL, Tyler DJ. Metabolic Effects of Doxorubicin on the Rat Liver Assessed With Hyperpolarized MRI and Metabolomics. Front Physiol 2021; 12:782745. [PMID: 35069242 PMCID: PMC8766499 DOI: 10.3389/fphys.2021.782745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 12/13/2021] [Indexed: 11/30/2022] Open
Abstract
Doxorubicin (DOX) is a successful chemotherapeutic widely used for the treatment of a range of cancers. However, DOX can have serious side-effects, with cardiotoxicity and hepatotoxicity being the most common events. Oxidative stress and changes in metabolism and bioenergetics are thought to be at the core of these toxicities. We have previously shown in a clinically-relevant rat model that a low DOX dose of 2 mg kg-1 week-1 for 6 weeks does not lead to cardiac functional decline or changes in cardiac carbohydrate metabolism, assessed with hyperpolarized [1-13C]pyruvate magnetic resonance spectroscopy (MRS). We now set out to assess whether there are any signs of liver damage or altered liver metabolism using this subclinical model. We found no increase in plasma alanine aminotransferase (ALT) activity, a measure of liver damage, following DOX treatment in rats at any time point. We also saw no changes in liver carbohydrate metabolism, using hyperpolarized [1-13C]pyruvate MRS. However, using metabolomic analysis of liver metabolite extracts at the final time point, we found an increase in most acyl-carnitine species as well as increases in high energy phosphates, citrate and markers of oxidative stress. This may indicate early signs of steatohepatitis, with increased and decompensated fatty acid uptake and oxidation, leading to oxidative stress.
Collapse
Affiliation(s)
- Kerstin N. Timm
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Department of Pharmacology, University of Oxford, Oxford, United Kingdom
- *Correspondence: Kerstin N. Timm,
| | - Vicky Ball
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Jack J. Miller
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Department of Physics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
- The MR Research Center, The PET Centre, Aarhus University Hospital, Aarhus University, Aarhus, Denmark
| | - Dragana Savic
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
| | - James A. West
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Julian L. Griffin
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Damian J. Tyler
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Centre for Clinical Magnetic Resonance Research, John Radcliffe Hospital, Oxford, United Kingdom
| |
Collapse
|
35
|
Datta K, Spielman D. MRI of [2- 13 C]Lactate without J-coupling artifacts. Magn Reson Med 2020; 85:1522-1539. [PMID: 33058240 DOI: 10.1002/mrm.28532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/19/2020] [Accepted: 09/03/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE Imaging of [2-13 C]lactate, a metabolic product of [2-13 C]pyruvate, is over considerable interest in hyperpolarized 13 C studies. However, artifact-free imaging of a J-coupled nuclear spin species can be challenging due to the peak-splitting induced by the spin-spin interactions. In this work, two new techniques resolving these J-modulated artifacts are presented. THEORY AND METHODS The Product Operator Formalism (POF) of density matrix theory is used to both numerically and analytically derive the coherences arising during radiofrequency excitation and readout of a J-coupled spin system. A combination of computer simulations and experiments with [2-13 C]lactate and 13 C-formate phantoms are then used to verify the performance of two imaging methods. In the first approach, a quadrature imaging technique is used to eliminate scalar coupling artifacts via the combination of in-phase and quadrature images acquired at echo times differing by 1/2J with an echoplanar readout. The second approach employs a highly narrowband RF excitation pulse to image a single peak from the J-coupled doublet. RESULTS Simulations using a numerical Shepp-Logan phantom, in vitro experiments using thermally polarized [2-13 C]lactate, thermally and hyperpolarized 13 C-formate phantoms, and in vivo imaging of [2-13 C]lactate produced in rat brain following injection of hyperpolarized [2-13 C]pyruvate show artifact-free images and demonstrate potential utility of these methods. CONCLUSION The quadrature imaging and the narrowband excitation techniques resolve the J-coupling induced ghosting and blurring artifacts present with conventional MRI of J-coupled signals such as [2-13 C]lactate.
Collapse
Affiliation(s)
- Keshav Datta
- Department of Radiology, Stanford University, Stanford, California, USA
| | - Daniel Spielman
- Department of Radiology, Stanford University, Stanford, California, USA
| |
Collapse
|
36
|
Chen J, Hackett EP, Kovacs Z, Malloy CR, Park JM. Assessment of hepatic pyruvate carboxylase activity using hyperpolarized [1- 13 C]-l-lactate. Magn Reson Med 2020; 85:1175-1182. [PMID: 32936474 DOI: 10.1002/mrm.28489] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 07/06/2020] [Accepted: 08/03/2020] [Indexed: 01/24/2023]
Abstract
PURPOSE To evaluate the utility of hyperpolarized [1-13 C]-l-lactate to detect hepatic pyruvate carboxylase activity in vivo under fed and fasted conditions. METHODS [1-13 C]-labeled sodium L-lactate was polarized using a dynamic nuclear polarizer. Polarization level and the T1 were measured in vitro in a 3 Telsa MR scanner. Two groups of healthy rats (fasted vs. fed) were prepared for in vivo studies. Each rat was anesthetized and intravenously injected with 60-mM hyperpolarized [1-13 C]-l-lactate, immediately followed by dynamic acquisition of 13 C (carbon-13) MR spectra from the liver at 3 Tesla. The dosage-dependence of the 13 C-products was also investigated by performing another injection of an equal volume of 30-mM hyperpolarized [1-13 C]-l-lactate. RESULTS T1 and liquid polarization level of [1-13 C]-l-lactate were estimated as 67.8 s and 40.0%, respectively. [1-13 C]pyruvate and [1-13 C]alanine, [13 C]bicarbonate ( HCO 3 - ) and [1-13 C]aspartate were produced from hyperpolarized [1-13 C]-l-lactate in rat liver. Smaller HCO 3 - and larger aspartate were measured in the fed group compared to the fasted group. Pyruvate and alanine production were increased in proportion to the lactate concentration, whereas the amount of HCO 3 - and aspartate production was consistent between 30-mM and 60-mM lactate injections. CONCLUSION This study demonstrates that a unique biomarker of pyruvate carboxylase flux, the appearance of [1-13 C]aspartate from [1-13 C]-l-lactate, is sensitive to nutritional state and may be monitored in vivo at 3 Tesla. Because [13 C] HCO 3 - is largely produced by pyruvate dehydrogenase flux, these results suggest that the ratio of [1-13 C]aspartate and [13 C] HCO 3 - (aspartate/ HCO 3 - ) reflects the saturable pyruvate carboxylase/pyruvate dehydrogenase enzyme activities.
Collapse
Affiliation(s)
- Jun Chen
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Edward P Hackett
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Zoltan Kovacs
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Craig R Malloy
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Jae Mo Park
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, Texas, USA.,Department of Electrical and Computer Engineering, The University of Texas at Dallas, Richardson, Texas, USA
| |
Collapse
|
37
|
Deh K, Granlund KL, Eskandari R, Kim N, Mamakhanyan A, Keshari KR. Dynamic volumetric hyperpolarized 13 C imaging with multi-echo EPI. Magn Reson Med 2020; 85:978-986. [PMID: 32820566 DOI: 10.1002/mrm.28466] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 07/07/2020] [Accepted: 07/15/2020] [Indexed: 11/10/2022]
Abstract
PURPOSE To generate dynamic, volumetric maps of hyperpolarized [1-13 C]pyruvate and its metabolic products in vivo. METHODS Maps of chemical species were generated with iterative least squares (IDEAL) reconstruction from multiecho echo-planar imaging (EPI) of phantoms of thermally polarized 13 C-labeled chemicals and mice injected with hyperpolarized [1-13 C]pyruvate on a preclinical 3T scanner. The quality of the IDEAL decomposition of single-shot and multishot phantom images was evaluated using quantitative results from a simple pulse-and-acquire sequence as the gold standard. Time course and area-under-the-curve plots were created to analyze the distribution of metabolites in vivo. RESULTS Improved separation of chemical species by IDEAL, evaluated by the amount of residual signal measured for chemicals not present in the phantoms, was observed as the number of EPI shots was increased from one to four. Dynamic three-dimensional metabolite maps of [1-13 C]pyruvate,[1-13 C]pyruvatehydrate, [1-13 C]lactate, [1-13 C]bicarbonate, and [1-13 C]alanine generated by IDEAL from interleaved multishot multiecho EPI of live mice were used to construct time course and area-under-the-curve graphs for the heart, kidneys, and liver, which showed good agreement with previously published results. CONCLUSIONS IDEAL decomposition of multishot multiecho 13C EPI images is a simple, yet robust method for generating high-quality dynamic volumetric maps of hyperpolarized [1-13 C]pyruvate and its products in vivo and has potential applications for the assessment of multiorgan metabolic phenomena.
Collapse
Affiliation(s)
- Kofi Deh
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Kristin L Granlund
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Roozbeh Eskandari
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Nathaniel Kim
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Arsen Mamakhanyan
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Kayvan R Keshari
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA.,Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| |
Collapse
|
38
|
Seenappa V, Joshi MB, Satyamoorthy K. Intricate Regulation of Phosphoenolpyruvate Carboxykinase (PEPCK) Isoforms in Normal Physiology and Disease. Curr Mol Med 2020; 19:247-272. [PMID: 30947672 DOI: 10.2174/1566524019666190404155801] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 03/25/2019] [Accepted: 03/27/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND The phosphoenolpyruvate carboxykinase (PEPCK) isoforms are considered as rate-limiting enzymes for gluconeogenesis and glyceroneogenesis pathways. PEPCK exhibits several interesting features such as a) organelle-specific isoforms (cytosolic and a mitochondrial) in vertebrate clade, b) tissue-specific expression of isoforms and c) organism-specific requirement of ATP or GTP as a cofactor. In higher organisms, PEPCK isoforms are intricately regulated and activated through several physiological and pathological stimuli such as corticoids, hormones, nutrient starvation and hypoxia. Isoform-specific transcriptional/translational regulation and their interplay in maintaining glucose homeostasis remain to be fully understood. Mounting evidence indicates the significant involvement of PEPCK isoforms in physiological processes (development and longevity) and in the progression of a variety of diseases (metabolic disorders, cancer, Smith-Magenis syndrome). OBJECTIVE The present systematic review aimed to assimilate existing knowledge of transcriptional and translational regulation of PEPCK isoforms derived from cell, animal and clinical models. CONCLUSION Based on current knowledge and extensive bioinformatics analysis, in this review we have provided a comparative (epi)genetic understanding of PCK1 and PCK2 genes encompassing regulatory elements, disease-associated polymorphisms, copy number variations, regulatory miRNAs and CpG densities. We have also discussed various exogenous and endogenous modulators of PEPCK isoforms and their signaling mechanisms. A comprehensive review of existing knowledge of PEPCK regulation and function may enable identification of the underlying gaps to design new pharmacological strategies and interventions for the diseases associated with gluconeogenesis.
Collapse
Affiliation(s)
- Venu Seenappa
- School of Life Sciences, Manipal Academy of Higher Education, Manipal - 576104, India
| | - Manjunath B Joshi
- School of Life Sciences, Manipal Academy of Higher Education, Manipal - 576104, India
| | - Kapaettu Satyamoorthy
- School of Life Sciences, Manipal Academy of Higher Education, Manipal - 576104, India
| |
Collapse
|
39
|
Kyun S, Yoo C, Hashimoto T, Tomi H, Teramoto N, Kim J, Lim K. Effects of exogenous lactate administration on fat metabolism and glycogen synthesis factors in rats. Phys Act Nutr 2020; 24:1-5. [PMID: 32698255 PMCID: PMC7451839 DOI: 10.20463/pan.2020.0008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/04/2020] [Accepted: 04/05/2020] [Indexed: 12/20/2022] Open
Abstract
PURPOSE Lactate has several beneficial roles as an energy resource and in metabolism. However, studies on the effects of oral administration of lactate on fat metabolism and glycogen synthesis are limited. Therefore, the purpose of the present study was to investigate how oral administration of lactate affects fat metabolism and glycogen synthesis factors at specific times (0, 30, 60, 120 min) after intake. METHODS Male Sprague Dawley (SD) rats (n = 24) were divided into four groups as follows: the control group (0 min) was sacrificed immediately after oral lactate administration; the test groups were administered lactate (2 g/kg) and sacrificed after 30, 60, and 120 min. Skeletal muscle and liver mRNA expression of GLUT4, FAT/CD36, PDH, CS, PC and GYS2 was assessed using reverse transcription-polymerase chain reaction. RESULTS GLUT4 and FAT/CD36 expression was significantly increased in skeletal muscle 120 min after lactate administration. PDH expression in skeletal muscle was altered at 30 and 120 min after lactate consumption, but was not significantly different compared to the control. CS, PC and GYS2 expression in liver was increased 60 min after lactate administration. CONCLUSION Our results indicate that exogenous lactate administration increases GLUT4 and FAT/CD36 expression in the muscle as well as glycogen synthase factors (PC, GYS2) in the liver after 60 min. Therefore, lactate supplementation may increase fat utilization as well as induce positive effects on glycogen synthesis in athletes.
Collapse
Affiliation(s)
- Sunghwan Kyun
- Department of physical education, Konkuk University, SeoulRepublic of Korea
| | - Choongsung Yoo
- Department of Health and Kinesiology, Texas A&M University, TexasUSA
| | - Takeshi Hashimoto
- Faculty of Sport & Health Science, Ritsumeikan University, ShigaJapan
| | - Hironori Tomi
- Center for Regional Sustainability and Innovation, Kochi University, KochiJapan
| | | | - Jisu Kim
- Physical Activity and Performance Institute (PAPI), Konkuk University, SeoulRepublic of Korea
- Department of Sports Medicine and Science, Konkuk University, SeoulRepublic of Korea
| | - Kiwon Lim
- Department of physical education, Konkuk University, SeoulRepublic of Korea
- Physical Activity and Performance Institute (PAPI), Konkuk University, SeoulRepublic of Korea
- Department of Sports Medicine and Science, Konkuk University, SeoulRepublic of Korea
| |
Collapse
|
40
|
Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance. SCI 2020. [DOI: 10.3390/sci2020043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a non-invasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects.
Collapse
|
41
|
Differentiation of Heterogeneous Mouse Liver from HCC by Hyperpolarized 13C Magnetic Resonance. SCI 2020. [DOI: 10.3390/sci2010003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The clinical characterization of small hepatocellular carcinoma (HCC) lesions in the liver and differentiation from heterogeneous inflammatory or fibrotic background is important for early detection and treatment. Metabolic monitoring of hyperpolarized 13C-labeled substrates has been suggested as a new avenue for diagnostic magnetic resonance. The metabolism of hyperpolarized [1-13C]pyruvate was monitored in mouse precision-cut liver slices (PCLS) of aged MDR2-KO mice, which served as a model for heterogeneous liver and HCC that develops similarly to the human disease. The relative in-cell activities of lactate dehydrogenase (LDH) to alanine transaminase (ALT) were found to be 0.40 ± 0.06 (n = 3) in healthy livers (from healthy mice), 0.90 ± 0.27 (n = 3) in heterogeneously inflamed liver, and 1.84 ± 0.46 (n = 3) in HCC. Thus, the in-cell LDH/ALT activities ratio was found to correlate with the progression of the disease. The results suggest that the LDH/ALT activities ratio may be useful in the assessment of liver disease. Because the technology used here is translational to both small liver samples that may be obtained from image-guided biopsy (i.e., ex vivo investigation) and to the intact liver (i.e., in a non-invasive MRI scan), these results may provide a path for differentiating heterogeneous liver from HCC in human subjects.
Collapse
|
42
|
Wattanavanitchakorn S, Ansari IH, El Azzouny M, Longacre MJ, Stoker SW, MacDonald MJ, Jitrapakdee S. Differential contribution of pyruvate carboxylation to anaplerosis and cataplerosis during non-gluconeogenic and gluconeogenic conditions in HepG2 cells. Arch Biochem Biophys 2019; 676:108124. [PMID: 31585072 DOI: 10.1016/j.abb.2019.108124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/13/2019] [Accepted: 10/01/2019] [Indexed: 11/30/2022]
Abstract
Pyruvate carboxylase (PC) is an anaplerotic enzyme that supplies oxaloacetate to mitochondria enabling the maintenance of other metabolic intermediates consumed by cataplerosis. Using liquid chromatography mass spectrometry (LC-MS) to measure metabolic intermediates derived from uniformly labeled 13C6-glucose or [3-13C]l-lactate, we investigated the contribution of PC to anaplerosis and cataplerosis in the liver cell line HepG2. Suppression of PC expression by short hairpin RNA lowered incorporation of 13C glucose incorporation into tricarboxylic acid cycle intermediates, aspartate, glutamate and sugar derivatives, indicating impaired cataplerosis. The perturbation of these biosynthetic pathways is accompanied by a marked decrease of cell viability and proliferation. In contrast, under gluconeogenic conditions where the HepG2 cells use lactate as a carbon source, pyruvate carboxylation contributed very little to the maintenance of these metabolites. Suppression of PC did not affect the percent incorporation of 13C-labeled carbon from lactate into citrate, α-ketoglutarate, malate, succinate as well as aspartate and glutamate, suggesting that under gluconeogenic condition, PC does not support cataplerosis from lactate.
Collapse
Affiliation(s)
| | - Israr H Ansari
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - Melissa J Longacre
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Scott W Stoker
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Michael J MacDonald
- Childrens Diabetes Center, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | - Sarawut Jitrapakdee
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand.
| |
Collapse
|
43
|
Real-time hyperpolarized 13C magnetic resonance detects increased pyruvate oxidation in pyruvate dehydrogenase kinase 2/4-double knockout mouse livers. Sci Rep 2019; 9:16480. [PMID: 31712597 PMCID: PMC6848094 DOI: 10.1038/s41598-019-52952-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 10/22/2019] [Indexed: 01/05/2023] Open
Abstract
The pyruvate dehydrogenase complex (PDH) critically regulates carbohydrate metabolism. Phosphorylation of PDH by one of the pyruvate dehydrogenase kinases 1-4 (PDK1-4) decreases the flux of carbohydrates into the TCA cycle. Inhibition of PDKs increases oxidative metabolism of carbohydrates, so targeting PDKs has emerged as an important therapeutic approach to manage various metabolic diseases. Therefore, it is highly desirable to begin to establish imaging tools for noninvasive measurements of PDH flux in rodent models. In this study, we used hyperpolarized (HP) 13C-magnetic resonance spectroscopy to study the impact of a PDK2/PDK4 double knockout (DKO) on pyruvate metabolism in perfused livers from lean and diet-induced obese (DIO) mice and validated the HP observations with high-resolution 13C-nuclear magnetic resonance (NMR) spectroscopy of tissue extracts and steady-state isotopomer analyses. We observed that PDK-deficient livers produce more HP-bicarbonate from HP-[1-13C]pyruvate than age-matched control livers. A steady-state 13C-NMR isotopomer analysis of tissue extracts confirmed that flux rates through PDH, as well as pyruvate carboxylase and pyruvate cycling activities, are significantly higher in PDK-deficient livers. Immunoblotting experiments confirmed that HP-bicarbonate production from HP-[1-13C]pyruvate parallels decreased phosphorylation of the PDH E1α subunit (pE1α) in liver tissue. Our findings indicate that combining real-time hyperpolarized 13C NMR spectroscopy and 13C isotopomer analysis provides quantitative insights into intermediary metabolism in PDK-knockout mice. We propose that this method will be useful in assessing metabolic disease states and developing therapies to improve PDH flux.
Collapse
|
44
|
Singh J, Suh EH, Sharma G, Khemtong C, Sherry AD, Kovacs Z. Probing carbohydrate metabolism using hyperpolarized 13 C-labeled molecules. NMR IN BIOMEDICINE 2019; 32:e4018. [PMID: 30474153 PMCID: PMC6579721 DOI: 10.1002/nbm.4018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 08/03/2018] [Accepted: 08/11/2018] [Indexed: 05/05/2023]
Abstract
Glycolysis is a fundamental metabolic process in all organisms. Anomalies in glucose metabolism are linked to various pathological conditions. In particular, elevated aerobic glycolysis is a characteristic feature of rapidly growing cells. Glycolysis and the closely related pentose phosphate pathway can be monitored in real time by hyperpolarized 13 C-labeled metabolic substrates such as 13 C-enriched, deuterated D-glucose derivatives, [2-13 C]-D-fructose, [2-13 C] dihydroxyacetone, [1-13 C]-D-glycerate, [1-13 C]-D-glucono-δ-lactone and [1-13 C] pyruvate in healthy and diseased tissues. Elevated glycolysis in tumors (the Warburg effect) was also successfully imaged using hyperpolarized [U-13 C6 , U-2 H7 ]-D-glucose, while the size of the preexisting lactate pool can be measured by 13 C MRS and/or MRI with hyperpolarized [1-13 C]pyruvate. This review summarizes the application of various hyperpolarized 13 C-labeled metabolites to the real-time monitoring of glycolysis and related metabolic processes in normal and diseased tissues.
Collapse
Affiliation(s)
- Jaspal Singh
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Eul Hyun Suh
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Gaurav Sharma
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Chalermchai Khemtong
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - A. Dean Sherry
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, TX, USA
| | - Zoltan Kovacs
- Advanced Imaging Research Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| |
Collapse
|
45
|
Wang ZJ, Ohliger MA, Larson PEZ, Gordon JW, Bok RA, Slater J, Villanueva-Meyer JE, Hess CP, Kurhanewicz J, Vigneron DB. Hyperpolarized 13C MRI: State of the Art and Future Directions. Radiology 2019; 291:273-284. [PMID: 30835184 DOI: 10.1148/radiol.2019182391] [Citation(s) in RCA: 190] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hyperpolarized (HP) carbon 13 (13C) MRI is an emerging molecular imaging method that allows rapid, noninvasive, and pathway-specific investigation of dynamic metabolic and physiologic processes that were previously inaccessible to imaging. This technique has enabled real-time in vivo investigations of metabolism that are central to a variety of diseases, including cancer, cardiovascular disease, and metabolic diseases of the liver and kidney. This review provides an overview of the methods of hyperpolarization and 13C probes investigated to date in preclinical models of disease. The article then discusses the progress that has been made in translating this technology for clinical investigation. In particular, the potential roles and emerging clinical applications of HP [1-13C]pyruvate MRI will be highlighted. The future directions to enable the adoption of this technology to advance the basic understanding of metabolism, to improve disease diagnosis, and to accelerate treatment assessment are also detailed.
Collapse
Affiliation(s)
- Zhen J Wang
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Michael A Ohliger
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Peder E Z Larson
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Jeremy W Gordon
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Robert A Bok
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - James Slater
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Javier E Villanueva-Meyer
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Christopher P Hess
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - John Kurhanewicz
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| | - Daniel B Vigneron
- From the Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143
| |
Collapse
|
46
|
Wang Z, Nielsen PM, Laustsen C, Bertelsen LB. Metabolic consequences of lactate dehydrogenase inhibition by oxamate in hyperglycemic proximal tubular cells. Exp Cell Res 2019; 378:51-56. [PMID: 30836064 DOI: 10.1016/j.yexcr.2019.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 01/14/2023]
Abstract
Diabetic kidney disease (DKD) is associated with altered metabolic patterns, leading to increased lactate production even in the presence of sufficient oxygen supply. Studies have shown hyperglycemia to be an important factor in determining development of DKD. Here we explore the metabolic consequences of lactate dehydrogenase (LDH) inhibition exerted by the LDH inhibitor, oxamate, in the isolated rat renal proximal tubular cells (NRK-52E) under hyperglycemic conditions. Cells treated with oxamate (100 mM) for 24 h, with or without high D-glucose (25 mM) load, were investigated with hyperpolarized [1-13C]pyruvate in a 1T NMR system. Respiratory measurements using an oxygen microsensor system was conducted. Oxamate treatment of cells with or without the presences of high D-glucose, reduced the lactate production/accumulation with 36.5% or 22.5% respectively. Reduced proliferation, hypertrophic effects, as well as elevated vascular endothelial growth factor (VEGF) expression in the NRK-52E cells were found. The increased glycolytic flux in high D-glucose cultured NRK-52E cells resulted in an upregulation of the cellular oxygen consumption rate upon treatment with oxamate. Our findings suggested that in vitro cultured NRK-52E cells exposed to hyperglycemic conditions, could redirect the glycolytic flux towards oxidative phosphorylation by LDH inhibition. This link between aerobic and anaerobic metabolism may be determined by the redox balance (NAD+/NADH ratio). In conclusion, hyperglycemic conditions and oxamate treatment alters the metabolic phenotype of NRK-52E cells towards increased oxygen utilization mediated by a decreased NAD+/NADH ratio, which in turn decreases cell proliferation/survival.
Collapse
Affiliation(s)
- Zhimin Wang
- MR Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Division of Endocrinology and Metabolic Diseases, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Per Mose Nielsen
- MR Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Christoffer Laustsen
- MR Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Lotte Bonde Bertelsen
- MR Research Centre, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
47
|
Lev-Cohain N, Sapir G, Harris T, Azar A, Gamliel A, Nardi-Schreiber A, Uppala S, Sosna J, Gomori JM, Katz-Brull R. Real-time ALT and LDH activities determined in viable precision-cut mouse liver slices using hyperpolarized [1- 13 C]pyruvate-Implications for studies on biopsied liver tissues. NMR IN BIOMEDICINE 2019; 32:e4043. [PMID: 30575159 DOI: 10.1002/nbm.4043] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/24/2018] [Accepted: 10/28/2018] [Indexed: 06/09/2023]
Abstract
Precision-cut liver slices (PCLS) are widely used in liver research as they provide a liver model with all liver cell types in their natural architecture. The purpose of this study was to demonstrate the use of PCLS for hyperpolarized metabolic investigation in a mouse model, for potential future application in liver biopsy cores. Fresh normal liver was harvested from six mice. 500 μm PCLS were prepared and placed in a 10 mm NMR tube in an NMR spectrometer and perfused continuously. 31 P spectra were acquired to evaluate the presence of adenosine triphosphate (ATP) and validate viability in all samples. Hyperpolarized [1-13 C]pyruvate was flushed into the NMR tube in the spectrometer. Consecutive 13 C NMR spectra were acquired immediately after the injection using both non-selective (five injections, two livers) and selective RF excitation (six injections, three livers). The 31 P spectra showed the characteristic signals of ATP, confirming the viability of the PCLS for more than 2.5 h in the spectrometer. After each of the [1-13 C]pyruvate injections, both [1-13 C]lactate and [1-13 C]alanine signals were detected. Selective RF excitation aimed at both [1-13 C]lactate and [1-13 C]alanine enabled better visualization and quantification of the metabolic activity. Using this acquisition approach only the newly formed metabolites are observed upon excitation, and their intensities relative to those of hyperpolarized pyruvate enable quantification of metabolite production rates. This rate of lactate and alanine production appeared to be constant throughout the measurement time, with alanine production about 2.3 times higher than lactate. In summary, the viability of PCLS in an NMR spectrometer was demonstrated and hyperpolarized [1-13 C]pyruvate metabolism was recorded. This study opens up the possibility of evaluating alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) activities in human liver biopsies, while preserving the tissue architecture and viability. In healthy, well-perfused liver slices the ratio of ALT to LDH activity is about 2.3.
Collapse
Affiliation(s)
- Naama Lev-Cohain
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Gal Sapir
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Talia Harris
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Assad Azar
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Ayelet Gamliel
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Atara Nardi-Schreiber
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Sivaranjan Uppala
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - J Moshe Gomori
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| | - Rachel Katz-Brull
- Department of Radiology, Hadassah Medical Center, Hebrew University of Jerusalem, The Faculty of Medicine, Jerusalem, Israel
| |
Collapse
|
48
|
Singh M, Josan S, Zhu M, Jhajharia A, Mayer D. Dynamic metabolic imaging of copolarized [2- 13 C]pyruvate and [1,4- 13 C 2 ]fumarate using 3D-spiral CSI with alternate spectral band excitation. Magn Reson Med 2019; 81:2869-2877. [PMID: 30687948 DOI: 10.1002/mrm.27639] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/08/2018] [Accepted: 11/26/2018] [Indexed: 12/18/2022]
Abstract
PURPOSE Developing a method for simultaneous metabolic imaging of copolarized [2-13 C]pyruvate and [1,4-13 C2 ]fumarate without chemical shift displacement artifacts that also permits different excitation flip angles for substrates and their metabolic products. METHODS The proposed pulse sequence consists of 2 frequency-selective radiofrequency pulses to alternatingly excite 2 spectral sub-bands each one followed by a fast 3D spiral CSI (3D-spCSI) readout. Spectrally selective radiofrequency pulses were designed to excite differential flip angles on substrates and products in each spectral sub-band. Number of signal averages analysis was used to determine a spectral width suitable to resolve the metabolites of interest in each of the sub-bands. RESULTS Phantom experiments verified the copolarization strategy and radiofrequency pulse design following differential flip angle used in our method. The signal behavior of the resonances in each sub-band was unaffected by the excitation of the respective alternate frequency band. Dynamic 3D 13 C CSI data demonstrated the ability of the sequence to image metabolites like pyruvate-hydrate, lactate, alanine, fumarate, and malate simultaneously and detect metabolic changes in the liver in a rat model of carbon tetrachloride-induced liver damage. CONCLUSION The presented method allows the dynamic CSI of a mixture of [2-13 C]pyruvate and [1,4-13 C2 ]fumarate without chemical shift displacement artifacts while also permitting the use of different flip angles for substrate and product signals. The method is potentially useful for combined in vivo imaging of inflammation and cell necrosis.
Collapse
Affiliation(s)
- Maninder Singh
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, Maryland
| | | | - Minjie Zhu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, Maryland
| | - Aditya Jhajharia
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, Maryland
| | - Dirk Mayer
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, Maryland
| |
Collapse
|
49
|
Kjærgaard U, Laustsen C, Nørlinger T, Tougaard RS, Mikkelsen E, Qi H, Bertelsen LB, Jessen N, Stødkilde‐Jørgensen H. Hyperpolarized [1- 13 C] pyruvate as a possible diagnostic tool in liver disease. Physiol Rep 2018; 6:e13943. [PMID: 30548433 PMCID: PMC6289910 DOI: 10.14814/phy2.13943] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/24/2018] [Accepted: 11/19/2018] [Indexed: 12/18/2022] Open
Abstract
Introduction of hyperpolarized magnetic resonance in preclinical studies and lately translation to patients provides new detailed in vivo information of metabolic flux in organs. Hyperpolarized magnetic resonance based on 13 C enriched pyruvate is performed without ionizing radiation and allows quantification of the pyruvate conversion products: alanine, lactate and bicarbonate in real time. Thus, this methodology has a promising potential for in vivo monitoring of energetic alterations in hepatic diseases. Using 13 C pyruvate, we investigated the metabolism in the porcine liver before and after intravenous injection of glucose. The overall mean lactate to pyruvate ratio increased significantly after the injection of glucose whereas the bicarbonate to pyruvate ratio was unaffected, representative of the levels of pyruvate entering the tricarboxylic acid cycle. Similarly, alanine to pyruvate ratio did not change. The increased lactate to pyruvate ratio over time showed an exponential correlation with insulin, glucagon and free fatty acids. Together, these data, obtained by hyperpolarized 13 C magnetic resonance spectroscopy and by blood sampling, indicate a hepatic metabolic shift in glucose utilization following a glucose challenge. Our findings demonstrate the capacity of hyperpolarized 13 C magnetic resonance spectroscopy for quantifying hepatic substrate metabolism in accordance with well-known physiological processes. When combined with concentration of blood insulin, glucagon and free fatty acids in the blood, the results indicate the potential of hyperpolarized magnetic resonance spectroscopy as a future clinical method for quantification of hepatic substrate metabolism.
Collapse
Affiliation(s)
- Uffe Kjærgaard
- MR Research CentreAarhus University HospitalAarhusDenmark
| | | | | | - Rasmus S. Tougaard
- MR Research CentreAarhus University HospitalAarhusDenmark
- Department of CardiologyAarhus University HospitalAarhusDenmark
| | | | - Haiyun Qi
- MR Research CentreAarhus University HospitalAarhusDenmark
| | | | - Niels Jessen
- Department of BiomedicineAarhus UniversityAarhusDenmark
- Department of Clinical PharmacologyAarhus University HospitalAarhusDenmark
| | | |
Collapse
|
50
|
Affiliation(s)
- Cornelius von Morze
- Department of Radiology and Biomedical Imaging, University of California, San Francisco
| |
Collapse
|